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			2461 lines
		
	
	
	
		
			85 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			2461 lines
		
	
	
	
		
			85 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
"""Core implementation of import.
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This module is NOT meant to be directly imported! It has been designed such
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that it can be bootstrapped into Python as the implementation of import. As
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such it requires the injection of specific modules and attributes in order to
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work. One should use importlib as the public-facing version of this module.
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"""
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#
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# IMPORTANT: Whenever making changes to this module, be sure to run
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# a top-level make in order to get the frozen version of the module
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# update. Not doing so will result in the Makefile to fail for
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# all others who don't have a ./python around to freeze the module
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# in the early stages of compilation.
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#
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# See importlib._setup() for what is injected into the global namespace.
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# When editing this code be aware that code executed at import time CANNOT
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# reference any injected objects! This includes not only global code but also
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# anything specified at the class level.
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# Bootstrap-related code ######################################################
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_CASE_INSENSITIVE_PLATFORMS = 'win', 'cygwin', 'darwin'
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def _make_relax_case():
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    if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS):
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        def _relax_case():
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						|
            """True if filenames must be checked case-insensitively."""
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            return b'PYTHONCASEOK' in _os.environ
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    else:
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        def _relax_case():
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						|
            """True if filenames must be checked case-insensitively."""
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            return False
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    return _relax_case
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def _w_long(x):
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    """Convert a 32-bit integer to little-endian."""
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    return (int(x) & 0xFFFFFFFF).to_bytes(4, 'little')
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def _r_long(int_bytes):
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						|
    """Convert 4 bytes in little-endian to an integer."""
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    return int.from_bytes(int_bytes, 'little')
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def _path_join(*path_parts):
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    """Replacement for os.path.join()."""
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    return path_sep.join([part.rstrip(path_separators)
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                          for part in path_parts if part])
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def _path_split(path):
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    """Replacement for os.path.split()."""
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    if len(path_separators) == 1:
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        front, _, tail = path.rpartition(path_sep)
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        return front, tail
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						|
    for x in reversed(path):
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						|
        if x in path_separators:
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            front, tail = path.rsplit(x, maxsplit=1)
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            return front, tail
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    return '', path
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def _path_stat(path):
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    """Stat the path.
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    Made a separate function to make it easier to override in experiments
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    (e.g. cache stat results).
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    """
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    return _os.stat(path)
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def _path_is_mode_type(path, mode):
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    """Test whether the path is the specified mode type."""
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    try:
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        stat_info = _path_stat(path)
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    except OSError:
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        return False
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    return (stat_info.st_mode & 0o170000) == mode
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def _path_isfile(path):
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    """Replacement for os.path.isfile."""
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    return _path_is_mode_type(path, 0o100000)
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def _path_isdir(path):
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    """Replacement for os.path.isdir."""
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						|
    if not path:
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        path = _os.getcwd()
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    return _path_is_mode_type(path, 0o040000)
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def _write_atomic(path, data, mode=0o666):
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    """Best-effort function to write data to a path atomically.
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    Be prepared to handle a FileExistsError if concurrent writing of the
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						|
    temporary file is attempted."""
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						|
    # id() is used to generate a pseudo-random filename.
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    path_tmp = '{}.{}'.format(path, id(path))
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    fd = _os.open(path_tmp,
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                  _os.O_EXCL | _os.O_CREAT | _os.O_WRONLY, mode & 0o666)
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    try:
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						|
        # We first write data to a temporary file, and then use os.replace() to
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						|
        # perform an atomic rename.
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						|
        with _io.FileIO(fd, 'wb') as file:
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						|
            file.write(data)
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        _os.replace(path_tmp, path)
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						|
    except OSError:
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						|
        try:
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						|
            _os.unlink(path_tmp)
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						|
        except OSError:
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            pass
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        raise
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def _wrap(new, old):
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    """Simple substitute for functools.update_wrapper."""
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    for replace in ['__module__', '__name__', '__qualname__', '__doc__']:
 | 
						|
        if hasattr(old, replace):
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						|
            setattr(new, replace, getattr(old, replace))
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    new.__dict__.update(old.__dict__)
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def _new_module(name):
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    return type(sys)(name)
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_code_type = type(_wrap.__code__)
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class _ManageReload:
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    """Manages the possible clean-up of sys.modules for load_module()."""
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    def __init__(self, name):
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        self._name = name
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						|
    def __enter__(self):
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        self._is_reload = self._name in sys.modules
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    def __exit__(self, *args):
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						|
        if any(arg is not None for arg in args) and not self._is_reload:
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            try:
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                del sys.modules[self._name]
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						|
            except KeyError:
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                pass
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# Module-level locking ########################################################
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# A dict mapping module names to weakrefs of _ModuleLock instances
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_module_locks = {}
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# A dict mapping thread ids to _ModuleLock instances
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_blocking_on = {}
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class _DeadlockError(RuntimeError):
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    pass
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class _ModuleLock:
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    """A recursive lock implementation which is able to detect deadlocks
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    (e.g. thread 1 trying to take locks A then B, and thread 2 trying to
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    take locks B then A).
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    """
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    def __init__(self, name):
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        self.lock = _thread.allocate_lock()
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        self.wakeup = _thread.allocate_lock()
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        self.name = name
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        self.owner = None
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        self.count = 0
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        self.waiters = 0
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    def has_deadlock(self):
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        # Deadlock avoidance for concurrent circular imports.
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        me = _thread.get_ident()
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        tid = self.owner
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        while True:
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            lock = _blocking_on.get(tid)
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						|
            if lock is None:
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                return False
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            tid = lock.owner
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						|
            if tid == me:
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                return True
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						|
    def acquire(self):
 | 
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        """
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        Acquire the module lock.  If a potential deadlock is detected,
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						|
        a _DeadlockError is raised.
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        Otherwise, the lock is always acquired and True is returned.
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        """
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        tid = _thread.get_ident()
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        _blocking_on[tid] = self
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        try:
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            while True:
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						|
                with self.lock:
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						|
                    if self.count == 0 or self.owner == tid:
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                        self.owner = tid
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                        self.count += 1
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                        return True
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						|
                    if self.has_deadlock():
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                        raise _DeadlockError('deadlock detected by %r' % self)
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						|
                    if self.wakeup.acquire(False):
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                        self.waiters += 1
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                # Wait for a release() call
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                self.wakeup.acquire()
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                self.wakeup.release()
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        finally:
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            del _blocking_on[tid]
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    def release(self):
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        tid = _thread.get_ident()
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						|
        with self.lock:
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						|
            if self.owner != tid:
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                raise RuntimeError('cannot release un-acquired lock')
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            assert self.count > 0
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            self.count -= 1
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						|
            if self.count == 0:
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                self.owner = None
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						|
                if self.waiters:
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                    self.waiters -= 1
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                    self.wakeup.release()
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						|
    def __repr__(self):
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						|
        return '_ModuleLock({!r}) at {}'.format(self.name, id(self))
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class _DummyModuleLock:
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						|
    """A simple _ModuleLock equivalent for Python builds without
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    multi-threading support."""
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    def __init__(self, name):
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        self.name = name
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        self.count = 0
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 | 
						|
    def acquire(self):
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						|
        self.count += 1
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        return True
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						|
    def release(self):
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						|
        if self.count == 0:
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            raise RuntimeError('cannot release un-acquired lock')
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        self.count -= 1
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    def __repr__(self):
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        return '_DummyModuleLock({!r}) at {}'.format(self.name, id(self))
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class _ModuleLockManager:
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    def __init__(self, name):
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        self._name = name
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        self._lock = None
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    def __enter__(self):
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        try:
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            self._lock = _get_module_lock(self._name)
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						|
        finally:
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            _imp.release_lock()
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        self._lock.acquire()
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    def __exit__(self, *args, **kwargs):
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        self._lock.release()
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# The following two functions are for consumption by Python/import.c.
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def _get_module_lock(name):
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    """Get or create the module lock for a given module name.
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						|
 | 
						|
    Should only be called with the import lock taken."""
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    lock = None
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						|
    try:
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						|
        lock = _module_locks[name]()
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						|
    except KeyError:
 | 
						|
        pass
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						|
    if lock is None:
 | 
						|
        if _thread is None:
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            lock = _DummyModuleLock(name)
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        else:
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            lock = _ModuleLock(name)
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        def cb(_):
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            del _module_locks[name]
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        _module_locks[name] = _weakref.ref(lock, cb)
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    return lock
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def _lock_unlock_module(name):
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    """Release the global import lock, and acquires then release the
 | 
						|
    module lock for a given module name.
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						|
    This is used to ensure a module is completely initialized, in the
 | 
						|
    event it is being imported by another thread.
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						|
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						|
    Should only be called with the import lock taken."""
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						|
    lock = _get_module_lock(name)
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						|
    _imp.release_lock()
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						|
    try:
 | 
						|
        lock.acquire()
 | 
						|
    except _DeadlockError:
 | 
						|
        # Concurrent circular import, we'll accept a partially initialized
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						|
        # module object.
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						|
        pass
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						|
    else:
 | 
						|
        lock.release()
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 | 
						|
# Frame stripping magic ###############################################
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def _call_with_frames_removed(f, *args, **kwds):
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						|
    """remove_importlib_frames in import.c will always remove sequences
 | 
						|
    of importlib frames that end with a call to this function
 | 
						|
 | 
						|
    Use it instead of a normal call in places where including the importlib
 | 
						|
    frames introduces unwanted noise into the traceback (e.g. when executing
 | 
						|
    module code)
 | 
						|
    """
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						|
    return f(*args, **kwds)
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						|
 | 
						|
 | 
						|
# Finder/loader utility code ###############################################
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						|
 | 
						|
# Magic word to reject .pyc files generated by other Python versions.
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						|
# It should change for each incompatible change to the bytecode.
 | 
						|
#
 | 
						|
# The value of CR and LF is incorporated so if you ever read or write
 | 
						|
# a .pyc file in text mode the magic number will be wrong; also, the
 | 
						|
# Apple MPW compiler swaps their values, botching string constants.
 | 
						|
#
 | 
						|
# The magic numbers must be spaced apart at least 2 values, as the
 | 
						|
# -U interpeter flag will cause MAGIC+1 being used. They have been
 | 
						|
# odd numbers for some time now.
 | 
						|
#
 | 
						|
# There were a variety of old schemes for setting the magic number.
 | 
						|
# The current working scheme is to increment the previous value by
 | 
						|
# 10.
 | 
						|
#
 | 
						|
# Starting with the adoption of PEP 3147 in Python 3.2, every bump in magic
 | 
						|
# number also includes a new "magic tag", i.e. a human readable string used
 | 
						|
# to represent the magic number in __pycache__ directories.  When you change
 | 
						|
# the magic number, you must also set a new unique magic tag.  Generally this
 | 
						|
# can be named after the Python major version of the magic number bump, but
 | 
						|
# it can really be anything, as long as it's different than anything else
 | 
						|
# that's come before.  The tags are included in the following table, starting
 | 
						|
# with Python 3.2a0.
 | 
						|
#
 | 
						|
# Known values:
 | 
						|
#  Python 1.5:   20121
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						|
#  Python 1.5.1: 20121
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						|
#     Python 1.5.2: 20121
 | 
						|
#     Python 1.6:   50428
 | 
						|
#     Python 2.0:   50823
 | 
						|
#     Python 2.0.1: 50823
 | 
						|
#     Python 2.1:   60202
 | 
						|
#     Python 2.1.1: 60202
 | 
						|
#     Python 2.1.2: 60202
 | 
						|
#     Python 2.2:   60717
 | 
						|
#     Python 2.3a0: 62011
 | 
						|
#     Python 2.3a0: 62021
 | 
						|
#     Python 2.3a0: 62011 (!)
 | 
						|
#     Python 2.4a0: 62041
 | 
						|
#     Python 2.4a3: 62051
 | 
						|
#     Python 2.4b1: 62061
 | 
						|
#     Python 2.5a0: 62071
 | 
						|
#     Python 2.5a0: 62081 (ast-branch)
 | 
						|
#     Python 2.5a0: 62091 (with)
 | 
						|
#     Python 2.5a0: 62092 (changed WITH_CLEANUP opcode)
 | 
						|
#     Python 2.5b3: 62101 (fix wrong code: for x, in ...)
 | 
						|
#     Python 2.5b3: 62111 (fix wrong code: x += yield)
 | 
						|
#     Python 2.5c1: 62121 (fix wrong lnotab with for loops and
 | 
						|
#                          storing constants that should have been removed)
 | 
						|
#     Python 2.5c2: 62131 (fix wrong code: for x, in ... in listcomp/genexp)
 | 
						|
#     Python 2.6a0: 62151 (peephole optimizations and STORE_MAP opcode)
 | 
						|
#     Python 2.6a1: 62161 (WITH_CLEANUP optimization)
 | 
						|
#     Python 2.7a0: 62171 (optimize list comprehensions/change LIST_APPEND)
 | 
						|
#     Python 2.7a0: 62181 (optimize conditional branches:
 | 
						|
#                          introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE)
 | 
						|
#     Python 2.7a0  62191 (introduce SETUP_WITH)
 | 
						|
#     Python 2.7a0  62201 (introduce BUILD_SET)
 | 
						|
#     Python 2.7a0  62211 (introduce MAP_ADD and SET_ADD)
 | 
						|
#     Python 3000:   3000
 | 
						|
#                    3010 (removed UNARY_CONVERT)
 | 
						|
#                    3020 (added BUILD_SET)
 | 
						|
#                    3030 (added keyword-only parameters)
 | 
						|
#                    3040 (added signature annotations)
 | 
						|
#                    3050 (print becomes a function)
 | 
						|
#                    3060 (PEP 3115 metaclass syntax)
 | 
						|
#                    3061 (string literals become unicode)
 | 
						|
#                    3071 (PEP 3109 raise changes)
 | 
						|
#                    3081 (PEP 3137 make __file__ and __name__ unicode)
 | 
						|
#                    3091 (kill str8 interning)
 | 
						|
#                    3101 (merge from 2.6a0, see 62151)
 | 
						|
#                    3103 (__file__ points to source file)
 | 
						|
#     Python 3.0a4: 3111 (WITH_CLEANUP optimization).
 | 
						|
#     Python 3.0a5: 3131 (lexical exception stacking, including POP_EXCEPT)
 | 
						|
#     Python 3.1a0: 3141 (optimize list, set and dict comprehensions:
 | 
						|
#             change LIST_APPEND and SET_ADD, add MAP_ADD)
 | 
						|
#     Python 3.1a0: 3151 (optimize conditional branches:
 | 
						|
#             introduce POP_JUMP_IF_FALSE and POP_JUMP_IF_TRUE)
 | 
						|
#     Python 3.2a0: 3160 (add SETUP_WITH)
 | 
						|
#                   tag: cpython-32
 | 
						|
#     Python 3.2a1: 3170 (add DUP_TOP_TWO, remove DUP_TOPX and ROT_FOUR)
 | 
						|
#                   tag: cpython-32
 | 
						|
#     Python 3.2a2  3180 (add DELETE_DEREF)
 | 
						|
#     Python 3.3a0  3190 __class__ super closure changed
 | 
						|
#     Python 3.3a0  3200 (__qualname__ added)
 | 
						|
#                      3210 (added size modulo 2**32 to the pyc header)
 | 
						|
#     Python 3.3a1  3220 (changed PEP 380 implementation)
 | 
						|
#     Python 3.3a4  3230 (revert changes to implicit __class__ closure)
 | 
						|
#     Python 3.4a1  3250 (evaluate positional default arguments before
 | 
						|
#                        keyword-only defaults)
 | 
						|
#     Python 3.4a1  3260 (add LOAD_CLASSDEREF; allow locals of class to override
 | 
						|
#                        free vars)
 | 
						|
#     Python 3.4a1  3270 (various tweaks to the __class__ closure)
 | 
						|
#     Python 3.4a1  3280 (remove implicit class argument)
 | 
						|
#     Python 3.4a4  3290 (changes to __qualname__ computation)
 | 
						|
#     Python 3.4a4  3300 (more changes to __qualname__ computation)
 | 
						|
#     Python 3.4rc2 3310 (alter __qualname__ computation)
 | 
						|
#
 | 
						|
# MAGIC must change whenever the bytecode emitted by the compiler may no
 | 
						|
# longer be understood by older implementations of the eval loop (usually
 | 
						|
# due to the addition of new opcodes).
 | 
						|
 | 
						|
MAGIC_NUMBER = (3310).to_bytes(2, 'little') + b'\r\n'
 | 
						|
_RAW_MAGIC_NUMBER = int.from_bytes(MAGIC_NUMBER, 'little')  # For import.c
 | 
						|
 | 
						|
_PYCACHE = '__pycache__'
 | 
						|
 | 
						|
SOURCE_SUFFIXES = ['.py']  # _setup() adds .pyw as needed.
 | 
						|
 | 
						|
DEBUG_BYTECODE_SUFFIXES = ['.pyc']
 | 
						|
OPTIMIZED_BYTECODE_SUFFIXES = ['.pyo']
 | 
						|
 | 
						|
def cache_from_source(path, debug_override=None):
 | 
						|
    """Given the path to a .py file, return the path to its .pyc/.pyo file.
 | 
						|
 | 
						|
    The .py file does not need to exist; this simply returns the path to the
 | 
						|
    .pyc/.pyo file calculated as if the .py file were imported.  The extension
 | 
						|
    will be .pyc unless sys.flags.optimize is non-zero, then it will be .pyo.
 | 
						|
 | 
						|
    If debug_override is not None, then it must be a boolean and is used in
 | 
						|
    place of sys.flags.optimize.
 | 
						|
 | 
						|
    If sys.implementation.cache_tag is None then NotImplementedError is raised.
 | 
						|
 | 
						|
    """
 | 
						|
    debug = not sys.flags.optimize if debug_override is None else debug_override
 | 
						|
    if debug:
 | 
						|
        suffixes = DEBUG_BYTECODE_SUFFIXES
 | 
						|
    else:
 | 
						|
        suffixes = OPTIMIZED_BYTECODE_SUFFIXES
 | 
						|
    head, tail = _path_split(path)
 | 
						|
    base, sep, rest = tail.rpartition('.')
 | 
						|
    tag = sys.implementation.cache_tag
 | 
						|
    if tag is None:
 | 
						|
        raise NotImplementedError('sys.implementation.cache_tag is None')
 | 
						|
    filename = ''.join([(base if base else rest), sep, tag, suffixes[0]])
 | 
						|
    return _path_join(head, _PYCACHE, filename)
 | 
						|
 | 
						|
 | 
						|
def source_from_cache(path):
 | 
						|
    """Given the path to a .pyc./.pyo file, return the path to its .py file.
 | 
						|
 | 
						|
    The .pyc/.pyo file does not need to exist; this simply returns the path to
 | 
						|
    the .py file calculated to correspond to the .pyc/.pyo file.  If path does
 | 
						|
    not conform to PEP 3147 format, ValueError will be raised. If
 | 
						|
    sys.implementation.cache_tag is None then NotImplementedError is raised.
 | 
						|
 | 
						|
    """
 | 
						|
    if sys.implementation.cache_tag is None:
 | 
						|
        raise NotImplementedError('sys.implementation.cache_tag is None')
 | 
						|
    head, pycache_filename = _path_split(path)
 | 
						|
    head, pycache = _path_split(head)
 | 
						|
    if pycache != _PYCACHE:
 | 
						|
        raise ValueError('{} not bottom-level directory in '
 | 
						|
                         '{!r}'.format(_PYCACHE, path))
 | 
						|
    if pycache_filename.count('.') != 2:
 | 
						|
        raise ValueError('expected only 2 dots in '
 | 
						|
                         '{!r}'.format(pycache_filename))
 | 
						|
    base_filename = pycache_filename.partition('.')[0]
 | 
						|
    return _path_join(head, base_filename + SOURCE_SUFFIXES[0])
 | 
						|
 | 
						|
 | 
						|
def _get_sourcefile(bytecode_path):
 | 
						|
    """Convert a bytecode file path to a source path (if possible).
 | 
						|
 | 
						|
    This function exists purely for backwards-compatibility for
 | 
						|
    PyImport_ExecCodeModuleWithFilenames() in the C API.
 | 
						|
 | 
						|
    """
 | 
						|
    if len(bytecode_path) == 0:
 | 
						|
        return None
 | 
						|
    rest, _, extension = bytecode_path.rpartition('.')
 | 
						|
    if not rest or extension.lower()[-3:-1] != 'py':
 | 
						|
        return bytecode_path
 | 
						|
    try:
 | 
						|
        source_path = source_from_cache(bytecode_path)
 | 
						|
    except (NotImplementedError, ValueError):
 | 
						|
        source_path = bytecode_path[:-1]
 | 
						|
    return source_path if _path_isfile(source_path) else bytecode_path
 | 
						|
 | 
						|
 | 
						|
def _calc_mode(path):
 | 
						|
    """Calculate the mode permissions for a bytecode file."""
 | 
						|
    try:
 | 
						|
        mode = _path_stat(path).st_mode
 | 
						|
    except OSError:
 | 
						|
        mode = 0o666
 | 
						|
    # We always ensure write access so we can update cached files
 | 
						|
    # later even when the source files are read-only on Windows (#6074)
 | 
						|
    mode |= 0o200
 | 
						|
    return mode
 | 
						|
 | 
						|
 | 
						|
def _verbose_message(message, *args, verbosity=1):
 | 
						|
    """Print the message to stderr if -v/PYTHONVERBOSE is turned on."""
 | 
						|
    if sys.flags.verbose >= verbosity:
 | 
						|
        if not message.startswith(('#', 'import ')):
 | 
						|
            message = '# ' + message
 | 
						|
        print(message.format(*args), file=sys.stderr)
 | 
						|
 | 
						|
 | 
						|
def _check_name(method):
 | 
						|
    """Decorator to verify that the module being requested matches the one the
 | 
						|
    loader can handle.
 | 
						|
 | 
						|
    The first argument (self) must define _name which the second argument is
 | 
						|
    compared against. If the comparison fails then ImportError is raised.
 | 
						|
 | 
						|
    """
 | 
						|
    def _check_name_wrapper(self, name=None, *args, **kwargs):
 | 
						|
        if name is None:
 | 
						|
            name = self.name
 | 
						|
        elif self.name != name:
 | 
						|
            raise ImportError('loader cannot handle %s' % name, name=name)
 | 
						|
        return method(self, name, *args, **kwargs)
 | 
						|
    _wrap(_check_name_wrapper, method)
 | 
						|
    return _check_name_wrapper
 | 
						|
 | 
						|
 | 
						|
def _requires_builtin(fxn):
 | 
						|
    """Decorator to verify the named module is built-in."""
 | 
						|
    def _requires_builtin_wrapper(self, fullname):
 | 
						|
        if fullname not in sys.builtin_module_names:
 | 
						|
            raise ImportError('{!r} is not a built-in module'.format(fullname),
 | 
						|
                              name=fullname)
 | 
						|
        return fxn(self, fullname)
 | 
						|
    _wrap(_requires_builtin_wrapper, fxn)
 | 
						|
    return _requires_builtin_wrapper
 | 
						|
 | 
						|
 | 
						|
def _requires_frozen(fxn):
 | 
						|
    """Decorator to verify the named module is frozen."""
 | 
						|
    def _requires_frozen_wrapper(self, fullname):
 | 
						|
        if not _imp.is_frozen(fullname):
 | 
						|
            raise ImportError('{!r} is not a frozen module'.format(fullname),
 | 
						|
                              name=fullname)
 | 
						|
        return fxn(self, fullname)
 | 
						|
    _wrap(_requires_frozen_wrapper, fxn)
 | 
						|
    return _requires_frozen_wrapper
 | 
						|
 | 
						|
 | 
						|
def _find_module_shim(self, fullname):
 | 
						|
    """Try to find a loader for the specified module by delegating to
 | 
						|
    self.find_loader().
 | 
						|
 | 
						|
    This method is deprecated in favor of finder.find_spec().
 | 
						|
 | 
						|
    """
 | 
						|
    # Call find_loader(). If it returns a string (indicating this
 | 
						|
    # is a namespace package portion), generate a warning and
 | 
						|
    # return None.
 | 
						|
    loader, portions = self.find_loader(fullname)
 | 
						|
    if loader is None and len(portions):
 | 
						|
        msg = 'Not importing directory {}: missing __init__'
 | 
						|
        _warnings.warn(msg.format(portions[0]), ImportWarning)
 | 
						|
    return loader
 | 
						|
 | 
						|
 | 
						|
def _load_module_shim(self, fullname):
 | 
						|
    """Load the specified module into sys.modules and return it.
 | 
						|
 | 
						|
    This method is deprecated.  Use loader.exec_module instead.
 | 
						|
 | 
						|
    """
 | 
						|
    spec = spec_from_loader(fullname, self)
 | 
						|
    methods = _SpecMethods(spec)
 | 
						|
    if fullname in sys.modules:
 | 
						|
        module = sys.modules[fullname]
 | 
						|
        methods.exec(module)
 | 
						|
        return sys.modules[fullname]
 | 
						|
    else:
 | 
						|
        return methods.load()
 | 
						|
 | 
						|
 | 
						|
def _validate_bytecode_header(data, source_stats=None, name=None, path=None):
 | 
						|
    """Validate the header of the passed-in bytecode against source_stats (if
 | 
						|
    given) and returning the bytecode that can be compiled by compile().
 | 
						|
 | 
						|
    All other arguments are used to enhance error reporting.
 | 
						|
 | 
						|
    ImportError is raised when the magic number is incorrect or the bytecode is
 | 
						|
    found to be stale. EOFError is raised when the data is found to be
 | 
						|
    truncated.
 | 
						|
 | 
						|
    """
 | 
						|
    exc_details = {}
 | 
						|
    if name is not None:
 | 
						|
        exc_details['name'] = name
 | 
						|
    else:
 | 
						|
        # To prevent having to make all messages have a conditional name.
 | 
						|
        name = '<bytecode>'
 | 
						|
    if path is not None:
 | 
						|
        exc_details['path'] = path
 | 
						|
    magic = data[:4]
 | 
						|
    raw_timestamp = data[4:8]
 | 
						|
    raw_size = data[8:12]
 | 
						|
    if magic != MAGIC_NUMBER:
 | 
						|
        message = 'bad magic number in {!r}: {!r}'.format(name, magic)
 | 
						|
        _verbose_message(message)
 | 
						|
        raise ImportError(message, **exc_details)
 | 
						|
    elif len(raw_timestamp) != 4:
 | 
						|
        message = 'reached EOF while reading timestamp in {!r}'.format(name)
 | 
						|
        _verbose_message(message)
 | 
						|
        raise EOFError(message)
 | 
						|
    elif len(raw_size) != 4:
 | 
						|
        message = 'reached EOF while reading size of source in {!r}'.format(name)
 | 
						|
        _verbose_message(message)
 | 
						|
        raise EOFError(message)
 | 
						|
    if source_stats is not None:
 | 
						|
        try:
 | 
						|
            source_mtime = int(source_stats['mtime'])
 | 
						|
        except KeyError:
 | 
						|
            pass
 | 
						|
        else:
 | 
						|
            if _r_long(raw_timestamp) != source_mtime:
 | 
						|
                message = 'bytecode is stale for {!r}'.format(name)
 | 
						|
                _verbose_message(message)
 | 
						|
                raise ImportError(message, **exc_details)
 | 
						|
        try:
 | 
						|
            source_size = source_stats['size'] & 0xFFFFFFFF
 | 
						|
        except KeyError:
 | 
						|
            pass
 | 
						|
        else:
 | 
						|
            if _r_long(raw_size) != source_size:
 | 
						|
                raise ImportError('bytecode is stale for {!r}'.format(name),
 | 
						|
                                  **exc_details)
 | 
						|
    return data[12:]
 | 
						|
 | 
						|
 | 
						|
def _compile_bytecode(data, name=None, bytecode_path=None, source_path=None):
 | 
						|
    """Compile bytecode as returned by _validate_bytecode_header()."""
 | 
						|
    code = marshal.loads(data)
 | 
						|
    if isinstance(code, _code_type):
 | 
						|
        _verbose_message('code object from {!r}', bytecode_path)
 | 
						|
        if source_path is not None:
 | 
						|
            _imp._fix_co_filename(code, source_path)
 | 
						|
        return code
 | 
						|
    else:
 | 
						|
        raise ImportError('Non-code object in {!r}'.format(bytecode_path),
 | 
						|
                          name=name, path=bytecode_path)
 | 
						|
 | 
						|
def _code_to_bytecode(code, mtime=0, source_size=0):
 | 
						|
    """Compile a code object into bytecode for writing out to a byte-compiled
 | 
						|
    file."""
 | 
						|
    data = bytearray(MAGIC_NUMBER)
 | 
						|
    data.extend(_w_long(mtime))
 | 
						|
    data.extend(_w_long(source_size))
 | 
						|
    data.extend(marshal.dumps(code))
 | 
						|
    return data
 | 
						|
 | 
						|
 | 
						|
def decode_source(source_bytes):
 | 
						|
    """Decode bytes representing source code and return the string.
 | 
						|
 | 
						|
    Universal newline support is used in the decoding.
 | 
						|
    """
 | 
						|
    import tokenize  # To avoid bootstrap issues.
 | 
						|
    source_bytes_readline = _io.BytesIO(source_bytes).readline
 | 
						|
    encoding = tokenize.detect_encoding(source_bytes_readline)
 | 
						|
    newline_decoder = _io.IncrementalNewlineDecoder(None, True)
 | 
						|
    return newline_decoder.decode(source_bytes.decode(encoding[0]))
 | 
						|
 | 
						|
 | 
						|
# Module specifications #######################################################
 | 
						|
 | 
						|
def _module_repr(module):
 | 
						|
    # The implementation of ModuleType__repr__().
 | 
						|
    loader = getattr(module, '__loader__', None)
 | 
						|
    if hasattr(loader, 'module_repr'):
 | 
						|
        # As soon as BuiltinImporter, FrozenImporter, and NamespaceLoader
 | 
						|
        # drop their implementations for module_repr. we can add a
 | 
						|
        # deprecation warning here.
 | 
						|
        try:
 | 
						|
            return loader.module_repr(module)
 | 
						|
        except Exception:
 | 
						|
            pass
 | 
						|
    try:
 | 
						|
        spec = module.__spec__
 | 
						|
    except AttributeError:
 | 
						|
        pass
 | 
						|
    else:
 | 
						|
        if spec is not None:
 | 
						|
            return _SpecMethods(spec).module_repr()
 | 
						|
 | 
						|
    # We could use module.__class__.__name__ instead of 'module' in the
 | 
						|
    # various repr permutations.
 | 
						|
    try:
 | 
						|
        name = module.__name__
 | 
						|
    except AttributeError:
 | 
						|
        name = '?'
 | 
						|
    try:
 | 
						|
        filename = module.__file__
 | 
						|
    except AttributeError:
 | 
						|
        if loader is None:
 | 
						|
            return '<module {!r}>'.format(name)
 | 
						|
        else:
 | 
						|
            return '<module {!r} ({!r})>'.format(name, loader)
 | 
						|
    else:
 | 
						|
        return '<module {!r} from {!r}>'.format(name, filename)
 | 
						|
 | 
						|
 | 
						|
class _installed_safely:
 | 
						|
 | 
						|
    def __init__(self, module):
 | 
						|
        self._module = module
 | 
						|
        self._spec = module.__spec__
 | 
						|
 | 
						|
    def __enter__(self):
 | 
						|
        # This must be done before putting the module in sys.modules
 | 
						|
        # (otherwise an optimization shortcut in import.c becomes
 | 
						|
        # wrong)
 | 
						|
        self._spec._initializing = True
 | 
						|
        sys.modules[self._spec.name] = self._module
 | 
						|
 | 
						|
    def __exit__(self, *args):
 | 
						|
        try:
 | 
						|
            spec = self._spec
 | 
						|
            if any(arg is not None for arg in args):
 | 
						|
                try:
 | 
						|
                    del sys.modules[spec.name]
 | 
						|
                except KeyError:
 | 
						|
                    pass
 | 
						|
            else:
 | 
						|
                _verbose_message('import {!r} # {!r}', spec.name, spec.loader)
 | 
						|
        finally:
 | 
						|
            self._spec._initializing = False
 | 
						|
 | 
						|
 | 
						|
class ModuleSpec:
 | 
						|
    """The specification for a module, used for loading.
 | 
						|
 | 
						|
    A module's spec is the source for information about the module.  For
 | 
						|
    data associated with the module, including source, use the spec's
 | 
						|
    loader.
 | 
						|
 | 
						|
    `name` is the absolute name of the module.  `loader` is the loader
 | 
						|
    to use when loading the module.  `parent` is the name of the
 | 
						|
    package the module is in.  The parent is derived from the name.
 | 
						|
 | 
						|
    `is_package` determines if the module is considered a package or
 | 
						|
    not.  On modules this is reflected by the `__path__` attribute.
 | 
						|
 | 
						|
    `origin` is the specific location used by the loader from which to
 | 
						|
    load the module, if that information is available.  When filename is
 | 
						|
    set, origin will match.
 | 
						|
 | 
						|
    `has_location` indicates that a spec's "origin" reflects a location.
 | 
						|
    When this is True, `__file__` attribute of the module is set.
 | 
						|
 | 
						|
    `cached` is the location of the cached bytecode file, if any.  It
 | 
						|
    corresponds to the `__cached__` attribute.
 | 
						|
 | 
						|
    `submodule_search_locations` is the sequence of path entries to
 | 
						|
    search when importing submodules.  If set, is_package should be
 | 
						|
    True--and False otherwise.
 | 
						|
 | 
						|
    Packages are simply modules that (may) have submodules.  If a spec
 | 
						|
    has a non-None value in `submodule_search_locations`, the import
 | 
						|
    system will consider modules loaded from the spec as packages.
 | 
						|
 | 
						|
    Only finders (see importlib.abc.MetaPathFinder and
 | 
						|
    importlib.abc.PathEntryFinder) should modify ModuleSpec instances.
 | 
						|
 | 
						|
    """
 | 
						|
 | 
						|
    def __init__(self, name, loader, *, origin=None, loader_state=None,
 | 
						|
                 is_package=None):
 | 
						|
        self.name = name
 | 
						|
        self.loader = loader
 | 
						|
        self.origin = origin
 | 
						|
        self.loader_state = loader_state
 | 
						|
        self.submodule_search_locations = [] if is_package else None
 | 
						|
 | 
						|
        # file-location attributes
 | 
						|
        self._set_fileattr = False
 | 
						|
        self._cached = None
 | 
						|
 | 
						|
    def __repr__(self):
 | 
						|
        args = ['name={!r}'.format(self.name),
 | 
						|
                'loader={!r}'.format(self.loader)]
 | 
						|
        if self.origin is not None:
 | 
						|
            args.append('origin={!r}'.format(self.origin))
 | 
						|
        if self.submodule_search_locations is not None:
 | 
						|
            args.append('submodule_search_locations={}'
 | 
						|
                        .format(self.submodule_search_locations))
 | 
						|
        return '{}({})'.format(self.__class__.__name__, ', '.join(args))
 | 
						|
 | 
						|
    def __eq__(self, other):
 | 
						|
        smsl = self.submodule_search_locations
 | 
						|
        try:
 | 
						|
            return (self.name == other.name and
 | 
						|
                    self.loader == other.loader and
 | 
						|
                    self.origin == other.origin and
 | 
						|
                    smsl == other.submodule_search_locations and
 | 
						|
                    self.cached == other.cached and
 | 
						|
                    self.has_location == other.has_location)
 | 
						|
        except AttributeError:
 | 
						|
            return False
 | 
						|
 | 
						|
    @property
 | 
						|
    def cached(self):
 | 
						|
        if self._cached is None:
 | 
						|
            if self.origin is not None and self._set_fileattr:
 | 
						|
                filename = self.origin
 | 
						|
                if filename.endswith(tuple(SOURCE_SUFFIXES)):
 | 
						|
                    try:
 | 
						|
                        self._cached = cache_from_source(filename)
 | 
						|
                    except NotImplementedError:
 | 
						|
                        pass
 | 
						|
                elif filename.endswith(tuple(BYTECODE_SUFFIXES)):
 | 
						|
                    self._cached = filename
 | 
						|
        return self._cached
 | 
						|
 | 
						|
    @cached.setter
 | 
						|
    def cached(self, cached):
 | 
						|
        self._cached = cached
 | 
						|
 | 
						|
    @property
 | 
						|
    def parent(self):
 | 
						|
        """The name of the module's parent."""
 | 
						|
        if self.submodule_search_locations is None:
 | 
						|
            return self.name.rpartition('.')[0]
 | 
						|
        else:
 | 
						|
            return self.name
 | 
						|
 | 
						|
    @property
 | 
						|
    def has_location(self):
 | 
						|
        return self._set_fileattr
 | 
						|
 | 
						|
    @has_location.setter
 | 
						|
    def has_location(self, value):
 | 
						|
        self._set_fileattr = bool(value)
 | 
						|
 | 
						|
 | 
						|
def spec_from_loader(name, loader, *, origin=None, is_package=None):
 | 
						|
    """Return a module spec based on various loader methods."""
 | 
						|
    if hasattr(loader, 'get_filename'):
 | 
						|
        if is_package is None:
 | 
						|
            return spec_from_file_location(name, loader=loader)
 | 
						|
        search = [] if is_package else None
 | 
						|
        return spec_from_file_location(name, loader=loader,
 | 
						|
                                       submodule_search_locations=search)
 | 
						|
 | 
						|
    if is_package is None:
 | 
						|
        if hasattr(loader, 'is_package'):
 | 
						|
            try:
 | 
						|
                is_package = loader.is_package(name)
 | 
						|
            except ImportError:
 | 
						|
                is_package = None  # aka, undefined
 | 
						|
        else:
 | 
						|
            # the default
 | 
						|
            is_package = False
 | 
						|
 | 
						|
    return ModuleSpec(name, loader, origin=origin, is_package=is_package)
 | 
						|
 | 
						|
 | 
						|
_POPULATE = object()
 | 
						|
 | 
						|
 | 
						|
def spec_from_file_location(name, location=None, *, loader=None,
 | 
						|
                            submodule_search_locations=_POPULATE):
 | 
						|
    """Return a module spec based on a file location.
 | 
						|
 | 
						|
    To indicate that the module is a package, set
 | 
						|
    submodule_search_locations to a list of directory paths.  An
 | 
						|
    empty list is sufficient, though its not otherwise useful to the
 | 
						|
    import system.
 | 
						|
 | 
						|
    The loader must take a spec as its only __init__() arg.
 | 
						|
 | 
						|
    """
 | 
						|
    if location is None:
 | 
						|
        # The caller may simply want a partially populated location-
 | 
						|
        # oriented spec.  So we set the location to a bogus value and
 | 
						|
        # fill in as much as we can.
 | 
						|
        location = '<unknown>'
 | 
						|
        if hasattr(loader, 'get_filename'):
 | 
						|
            # ExecutionLoader
 | 
						|
            try:
 | 
						|
                location = loader.get_filename(name)
 | 
						|
            except ImportError:
 | 
						|
                pass
 | 
						|
 | 
						|
    # If the location is on the filesystem, but doesn't actually exist,
 | 
						|
    # we could return None here, indicating that the location is not
 | 
						|
    # valid.  However, we don't have a good way of testing since an
 | 
						|
    # indirect location (e.g. a zip file or URL) will look like a
 | 
						|
    # non-existent file relative to the filesystem.
 | 
						|
 | 
						|
    spec = ModuleSpec(name, loader, origin=location)
 | 
						|
    spec._set_fileattr = True
 | 
						|
 | 
						|
    # Pick a loader if one wasn't provided.
 | 
						|
    if loader is None:
 | 
						|
        for loader_class, suffixes in _get_supported_file_loaders():
 | 
						|
            if location.endswith(tuple(suffixes)):
 | 
						|
                loader = loader_class(name, location)
 | 
						|
                spec.loader = loader
 | 
						|
                break
 | 
						|
        else:
 | 
						|
            return None
 | 
						|
 | 
						|
    # Set submodule_search_paths appropriately.
 | 
						|
    if submodule_search_locations is _POPULATE:
 | 
						|
        # Check the loader.
 | 
						|
        if hasattr(loader, 'is_package'):
 | 
						|
            try:
 | 
						|
                is_package = loader.is_package(name)
 | 
						|
            except ImportError:
 | 
						|
                pass
 | 
						|
            else:
 | 
						|
                if is_package:
 | 
						|
                    spec.submodule_search_locations = []
 | 
						|
    else:
 | 
						|
        spec.submodule_search_locations = submodule_search_locations
 | 
						|
    if spec.submodule_search_locations == []:
 | 
						|
        if location:
 | 
						|
            dirname = _path_split(location)[0]
 | 
						|
            spec.submodule_search_locations.append(dirname)
 | 
						|
 | 
						|
    return spec
 | 
						|
 | 
						|
 | 
						|
def _spec_from_module(module, loader=None, origin=None):
 | 
						|
    # This function is meant for use in _setup().
 | 
						|
    try:
 | 
						|
        spec = module.__spec__
 | 
						|
    except AttributeError:
 | 
						|
        pass
 | 
						|
    else:
 | 
						|
        if spec is not None:
 | 
						|
            return spec
 | 
						|
 | 
						|
    name = module.__name__
 | 
						|
    if loader is None:
 | 
						|
        try:
 | 
						|
            loader = module.__loader__
 | 
						|
        except AttributeError:
 | 
						|
            # loader will stay None.
 | 
						|
            pass
 | 
						|
    try:
 | 
						|
        location = module.__file__
 | 
						|
    except AttributeError:
 | 
						|
        location = None
 | 
						|
    if origin is None:
 | 
						|
        if location is None:
 | 
						|
            try:
 | 
						|
                origin = loader._ORIGIN
 | 
						|
            except AttributeError:
 | 
						|
                origin = None
 | 
						|
        else:
 | 
						|
            origin = location
 | 
						|
    try:
 | 
						|
        cached = module.__cached__
 | 
						|
    except AttributeError:
 | 
						|
        cached = None
 | 
						|
    try:
 | 
						|
        submodule_search_locations = list(module.__path__)
 | 
						|
    except AttributeError:
 | 
						|
        submodule_search_locations = None
 | 
						|
 | 
						|
    spec = ModuleSpec(name, loader, origin=origin)
 | 
						|
    spec._set_fileattr = False if location is None else True
 | 
						|
    spec.cached = cached
 | 
						|
    spec.submodule_search_locations = submodule_search_locations
 | 
						|
    return spec
 | 
						|
 | 
						|
 | 
						|
class _SpecMethods:
 | 
						|
 | 
						|
    """Convenience wrapper around spec objects to provide spec-specific
 | 
						|
    methods."""
 | 
						|
 | 
						|
    # The various spec_from_* functions could be made factory methods here.
 | 
						|
 | 
						|
    def __init__(self, spec):
 | 
						|
        self.spec = spec
 | 
						|
 | 
						|
    def module_repr(self):
 | 
						|
        """Return the repr to use for the module."""
 | 
						|
        # We mostly replicate _module_repr() using the spec attributes.
 | 
						|
        spec = self.spec
 | 
						|
        name = '?' if spec.name is None else spec.name
 | 
						|
        if spec.origin is None:
 | 
						|
            if spec.loader is None:
 | 
						|
                return '<module {!r}>'.format(name)
 | 
						|
            else:
 | 
						|
                return '<module {!r} ({!r})>'.format(name, spec.loader)
 | 
						|
        else:
 | 
						|
            if spec.has_location:
 | 
						|
                return '<module {!r} from {!r}>'.format(name, spec.origin)
 | 
						|
            else:
 | 
						|
                return '<module {!r} ({})>'.format(spec.name, spec.origin)
 | 
						|
 | 
						|
    def init_module_attrs(self, module, *, _override=False, _force_name=True):
 | 
						|
        """Set the module's attributes.
 | 
						|
 | 
						|
        All missing import-related module attributes will be set.  Here
 | 
						|
        is how the spec attributes map onto the module:
 | 
						|
 | 
						|
        spec.name -> module.__name__
 | 
						|
        spec.loader -> module.__loader__
 | 
						|
        spec.parent -> module.__package__
 | 
						|
        spec -> module.__spec__
 | 
						|
 | 
						|
        Optional:
 | 
						|
        spec.origin -> module.__file__ (if spec.set_fileattr is true)
 | 
						|
        spec.cached -> module.__cached__ (if __file__ also set)
 | 
						|
        spec.submodule_search_locations -> module.__path__ (if set)
 | 
						|
 | 
						|
        """
 | 
						|
        spec = self.spec
 | 
						|
 | 
						|
        # The passed in module may be not support attribute assignment,
 | 
						|
        # in which case we simply don't set the attributes.
 | 
						|
 | 
						|
        # __name__
 | 
						|
        if (_override or _force_name or
 | 
						|
            getattr(module, '__name__', None) is None):
 | 
						|
            try:
 | 
						|
                module.__name__ = spec.name
 | 
						|
            except AttributeError:
 | 
						|
                pass
 | 
						|
 | 
						|
        # __loader__
 | 
						|
        if _override or getattr(module, '__loader__', None) is None:
 | 
						|
            loader = spec.loader
 | 
						|
            if loader is None:
 | 
						|
                # A backward compatibility hack.
 | 
						|
                if spec.submodule_search_locations is not None:
 | 
						|
                    loader = _NamespaceLoader.__new__(_NamespaceLoader)
 | 
						|
                    loader._path = spec.submodule_search_locations
 | 
						|
            try:
 | 
						|
                module.__loader__ = loader
 | 
						|
            except AttributeError:
 | 
						|
                pass
 | 
						|
 | 
						|
        # __package__
 | 
						|
        if _override or getattr(module, '__package__', None) is None:
 | 
						|
            try:
 | 
						|
                module.__package__ = spec.parent
 | 
						|
            except AttributeError:
 | 
						|
                pass
 | 
						|
 | 
						|
        # __spec__
 | 
						|
        try:
 | 
						|
            module.__spec__ = spec
 | 
						|
        except AttributeError:
 | 
						|
            pass
 | 
						|
 | 
						|
        # __path__
 | 
						|
        if _override or getattr(module, '__path__', None) is None:
 | 
						|
            if spec.submodule_search_locations is not None:
 | 
						|
                try:
 | 
						|
                    module.__path__ = spec.submodule_search_locations
 | 
						|
                except AttributeError:
 | 
						|
                    pass
 | 
						|
 | 
						|
        if spec.has_location:
 | 
						|
            # __file__
 | 
						|
            if _override or getattr(module, '__file__', None) is None:
 | 
						|
                try:
 | 
						|
                    module.__file__ = spec.origin
 | 
						|
                except AttributeError:
 | 
						|
                    pass
 | 
						|
 | 
						|
            # __cached__
 | 
						|
            if _override or getattr(module, '__cached__', None) is None:
 | 
						|
                if spec.cached is not None:
 | 
						|
                    try:
 | 
						|
                        module.__cached__ = spec.cached
 | 
						|
                    except AttributeError:
 | 
						|
                        pass
 | 
						|
 | 
						|
    def create(self):
 | 
						|
        """Return a new module to be loaded.
 | 
						|
 | 
						|
        The import-related module attributes are also set with the
 | 
						|
        appropriate values from the spec.
 | 
						|
 | 
						|
        """
 | 
						|
        spec = self.spec
 | 
						|
        # Typically loaders will not implement create_module().
 | 
						|
        if hasattr(spec.loader, 'create_module'):
 | 
						|
            # If create_module() returns `None` it means the default
 | 
						|
            # module creation should be used.
 | 
						|
            module = spec.loader.create_module(spec)
 | 
						|
        else:
 | 
						|
            module = None
 | 
						|
        if module is None:
 | 
						|
            # This must be done before open() is ever called as the 'io'
 | 
						|
            # module implicitly imports 'locale' and would otherwise
 | 
						|
            # trigger an infinite loop.
 | 
						|
            module = _new_module(spec.name)
 | 
						|
        self.init_module_attrs(module)
 | 
						|
        return module
 | 
						|
 | 
						|
    def _exec(self, module):
 | 
						|
        """Do everything necessary to execute the module.
 | 
						|
 | 
						|
        The namespace of `module` is used as the target of execution.
 | 
						|
        This method uses the loader's `exec_module()` method.
 | 
						|
 | 
						|
        """
 | 
						|
        self.spec.loader.exec_module(module)
 | 
						|
 | 
						|
    # Used by importlib.reload() and _load_module_shim().
 | 
						|
    def exec(self, module):
 | 
						|
        """Execute the spec in an existing module's namespace."""
 | 
						|
        name = self.spec.name
 | 
						|
        _imp.acquire_lock()
 | 
						|
        with _ModuleLockManager(name):
 | 
						|
            if sys.modules.get(name) is not module:
 | 
						|
                msg = 'module {!r} not in sys.modules'.format(name)
 | 
						|
                raise ImportError(msg, name=name)
 | 
						|
            if self.spec.loader is None:
 | 
						|
                if self.spec.submodule_search_locations is None:
 | 
						|
                    raise ImportError('missing loader', name=self.spec.name)
 | 
						|
                # namespace package
 | 
						|
                self.init_module_attrs(module, _override=True)
 | 
						|
                return module
 | 
						|
            self.init_module_attrs(module, _override=True)
 | 
						|
            if not hasattr(self.spec.loader, 'exec_module'):
 | 
						|
                # (issue19713) Once BuiltinImporter and ExtensionFileLoader
 | 
						|
                # have exec_module() implemented, we can add a deprecation
 | 
						|
                # warning here.
 | 
						|
                self.spec.loader.load_module(name)
 | 
						|
            else:
 | 
						|
                self._exec(module)
 | 
						|
        return sys.modules[name]
 | 
						|
 | 
						|
    def _load_backward_compatible(self):
 | 
						|
        # (issue19713) Once BuiltinImporter and ExtensionFileLoader
 | 
						|
        # have exec_module() implemented, we can add a deprecation
 | 
						|
        # warning here.
 | 
						|
        spec = self.spec
 | 
						|
        spec.loader.load_module(spec.name)
 | 
						|
        # The module must be in sys.modules at this point!
 | 
						|
        module = sys.modules[spec.name]
 | 
						|
        if getattr(module, '__loader__', None) is None:
 | 
						|
            try:
 | 
						|
                module.__loader__ = spec.loader
 | 
						|
            except AttributeError:
 | 
						|
                pass
 | 
						|
        if getattr(module, '__package__', None) is None:
 | 
						|
            try:
 | 
						|
                # Since module.__path__ may not line up with
 | 
						|
                # spec.submodule_search_paths, we can't necessarily rely
 | 
						|
                # on spec.parent here.
 | 
						|
                module.__package__ = module.__name__
 | 
						|
                if not hasattr(module, '__path__'):
 | 
						|
                    module.__package__ = spec.name.rpartition('.')[0]
 | 
						|
            except AttributeError:
 | 
						|
                pass
 | 
						|
        if getattr(module, '__spec__', None) is None:
 | 
						|
            try:
 | 
						|
                module.__spec__ = spec
 | 
						|
            except AttributeError:
 | 
						|
                pass
 | 
						|
        return module
 | 
						|
 | 
						|
    def _load_unlocked(self):
 | 
						|
        # A helper for direct use by the import system.
 | 
						|
        if self.spec.loader is not None:
 | 
						|
            # not a namespace package
 | 
						|
            if not hasattr(self.spec.loader, 'exec_module'):
 | 
						|
                return self._load_backward_compatible()
 | 
						|
 | 
						|
        module = self.create()
 | 
						|
        with _installed_safely(module):
 | 
						|
            if self.spec.loader is None:
 | 
						|
                if self.spec.submodule_search_locations is None:
 | 
						|
                    raise ImportError('missing loader', name=self.spec.name)
 | 
						|
                # A namespace package so do nothing.
 | 
						|
            else:
 | 
						|
                self._exec(module)
 | 
						|
 | 
						|
        # We don't ensure that the import-related module attributes get
 | 
						|
        # set in the sys.modules replacement case.  Such modules are on
 | 
						|
        # their own.
 | 
						|
        return sys.modules[self.spec.name]
 | 
						|
 | 
						|
    # A method used during testing of _load_unlocked() and by
 | 
						|
    # _load_module_shim().
 | 
						|
    def load(self):
 | 
						|
        """Return a new module object, loaded by the spec's loader.
 | 
						|
 | 
						|
        The module is not added to its parent.
 | 
						|
 | 
						|
        If a module is already in sys.modules, that existing module gets
 | 
						|
        clobbered.
 | 
						|
 | 
						|
        """
 | 
						|
        _imp.acquire_lock()
 | 
						|
        with _ModuleLockManager(self.spec.name):
 | 
						|
            return self._load_unlocked()
 | 
						|
 | 
						|
 | 
						|
def _fix_up_module(ns, name, pathname, cpathname=None):
 | 
						|
    # This function is used by PyImport_ExecCodeModuleObject().
 | 
						|
    loader = ns.get('__loader__')
 | 
						|
    spec = ns.get('__spec__')
 | 
						|
    if not loader:
 | 
						|
        if spec:
 | 
						|
            loader = spec.loader
 | 
						|
        elif pathname == cpathname:
 | 
						|
            loader = SourcelessFileLoader(name, pathname)
 | 
						|
        else:
 | 
						|
            loader = SourceFileLoader(name, pathname)
 | 
						|
    if not spec:
 | 
						|
        spec = spec_from_file_location(name, pathname, loader=loader)
 | 
						|
    try:
 | 
						|
        ns['__spec__'] = spec
 | 
						|
        ns['__loader__'] = loader
 | 
						|
        ns['__file__'] = pathname
 | 
						|
        ns['__cached__'] = cpathname
 | 
						|
    except Exception:
 | 
						|
        # Not important enough to report.
 | 
						|
        pass
 | 
						|
 | 
						|
 | 
						|
# Loaders #####################################################################
 | 
						|
 | 
						|
class BuiltinImporter:
 | 
						|
 | 
						|
    """Meta path import for built-in modules.
 | 
						|
 | 
						|
    All methods are either class or static methods to avoid the need to
 | 
						|
    instantiate the class.
 | 
						|
 | 
						|
    """
 | 
						|
 | 
						|
    @staticmethod
 | 
						|
    def module_repr(module):
 | 
						|
        """Return repr for the module.
 | 
						|
 | 
						|
        The method is deprecated.  The import machinery does the job itself.
 | 
						|
 | 
						|
        """
 | 
						|
        return '<module {!r} (built-in)>'.format(module.__name__)
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def find_spec(cls, fullname, path=None, target=None):
 | 
						|
        if path is not None:
 | 
						|
            return None
 | 
						|
        if _imp.is_builtin(fullname):
 | 
						|
            return spec_from_loader(fullname, cls, origin='built-in')
 | 
						|
        else:
 | 
						|
            return None
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def find_module(cls, fullname, path=None):
 | 
						|
        """Find the built-in module.
 | 
						|
 | 
						|
        If 'path' is ever specified then the search is considered a failure.
 | 
						|
 | 
						|
        This method is deprecated.  Use find_spec() instead.
 | 
						|
 | 
						|
        """
 | 
						|
        spec = cls.find_spec(fullname, path)
 | 
						|
        return spec.loader if spec is not None else None
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    @_requires_builtin
 | 
						|
    def load_module(cls, fullname):
 | 
						|
        """Load a built-in module."""
 | 
						|
        # Once an exec_module() implementation is added we can also
 | 
						|
        # add a deprecation warning here.
 | 
						|
        with _ManageReload(fullname):
 | 
						|
            module = _call_with_frames_removed(_imp.init_builtin, fullname)
 | 
						|
        module.__loader__ = cls
 | 
						|
        module.__package__ = ''
 | 
						|
        return module
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    @_requires_builtin
 | 
						|
    def get_code(cls, fullname):
 | 
						|
        """Return None as built-in modules do not have code objects."""
 | 
						|
        return None
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    @_requires_builtin
 | 
						|
    def get_source(cls, fullname):
 | 
						|
        """Return None as built-in modules do not have source code."""
 | 
						|
        return None
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    @_requires_builtin
 | 
						|
    def is_package(cls, fullname):
 | 
						|
        """Return False as built-in modules are never packages."""
 | 
						|
        return False
 | 
						|
 | 
						|
 | 
						|
class FrozenImporter:
 | 
						|
 | 
						|
    """Meta path import for frozen modules.
 | 
						|
 | 
						|
    All methods are either class or static methods to avoid the need to
 | 
						|
    instantiate the class.
 | 
						|
 | 
						|
    """
 | 
						|
 | 
						|
    @staticmethod
 | 
						|
    def module_repr(m):
 | 
						|
        """Return repr for the module.
 | 
						|
 | 
						|
        The method is deprecated.  The import machinery does the job itself.
 | 
						|
 | 
						|
        """
 | 
						|
        return '<module {!r} (frozen)>'.format(m.__name__)
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def find_spec(cls, fullname, path=None, target=None):
 | 
						|
        if _imp.is_frozen(fullname):
 | 
						|
            return spec_from_loader(fullname, cls, origin='frozen')
 | 
						|
        else:
 | 
						|
            return None
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def find_module(cls, fullname, path=None):
 | 
						|
        """Find a frozen module.
 | 
						|
 | 
						|
        This method is deprecated.  Use find_spec() instead.
 | 
						|
 | 
						|
        """
 | 
						|
        return cls if _imp.is_frozen(fullname) else None
 | 
						|
 | 
						|
    @staticmethod
 | 
						|
    def exec_module(module):
 | 
						|
        name = module.__spec__.name
 | 
						|
        if not _imp.is_frozen(name):
 | 
						|
            raise ImportError('{!r} is not a frozen module'.format(name),
 | 
						|
                              name=name)
 | 
						|
        code = _call_with_frames_removed(_imp.get_frozen_object, name)
 | 
						|
        exec(code, module.__dict__)
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def load_module(cls, fullname):
 | 
						|
        """Load a frozen module.
 | 
						|
 | 
						|
        This method is deprecated.  Use exec_module() instead.
 | 
						|
 | 
						|
        """
 | 
						|
        return _load_module_shim(cls, fullname)
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    @_requires_frozen
 | 
						|
    def get_code(cls, fullname):
 | 
						|
        """Return the code object for the frozen module."""
 | 
						|
        return _imp.get_frozen_object(fullname)
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    @_requires_frozen
 | 
						|
    def get_source(cls, fullname):
 | 
						|
        """Return None as frozen modules do not have source code."""
 | 
						|
        return None
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    @_requires_frozen
 | 
						|
    def is_package(cls, fullname):
 | 
						|
        """Return True if the frozen module is a package."""
 | 
						|
        return _imp.is_frozen_package(fullname)
 | 
						|
 | 
						|
 | 
						|
class WindowsRegistryFinder:
 | 
						|
 | 
						|
    """Meta path finder for modules declared in the Windows registry."""
 | 
						|
 | 
						|
    REGISTRY_KEY = (
 | 
						|
        'Software\\Python\\PythonCore\\{sys_version}'
 | 
						|
        '\\Modules\\{fullname}')
 | 
						|
    REGISTRY_KEY_DEBUG = (
 | 
						|
        'Software\\Python\\PythonCore\\{sys_version}'
 | 
						|
        '\\Modules\\{fullname}\\Debug')
 | 
						|
    DEBUG_BUILD = False  # Changed in _setup()
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def _open_registry(cls, key):
 | 
						|
        try:
 | 
						|
            return _winreg.OpenKey(_winreg.HKEY_CURRENT_USER, key)
 | 
						|
        except OSError:
 | 
						|
            return _winreg.OpenKey(_winreg.HKEY_LOCAL_MACHINE, key)
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def _search_registry(cls, fullname):
 | 
						|
        if cls.DEBUG_BUILD:
 | 
						|
            registry_key = cls.REGISTRY_KEY_DEBUG
 | 
						|
        else:
 | 
						|
            registry_key = cls.REGISTRY_KEY
 | 
						|
        key = registry_key.format(fullname=fullname,
 | 
						|
                                  sys_version=sys.version[:3])
 | 
						|
        try:
 | 
						|
            with cls._open_registry(key) as hkey:
 | 
						|
                filepath = _winreg.QueryValue(hkey, '')
 | 
						|
        except OSError:
 | 
						|
            return None
 | 
						|
        return filepath
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def find_spec(cls, fullname, path=None, target=None):
 | 
						|
        filepath = cls._search_registry(fullname)
 | 
						|
        if filepath is None:
 | 
						|
            return None
 | 
						|
        try:
 | 
						|
            _path_stat(filepath)
 | 
						|
        except OSError:
 | 
						|
            return None
 | 
						|
        for loader, suffixes in _get_supported_file_loaders():
 | 
						|
            if filepath.endswith(tuple(suffixes)):
 | 
						|
                spec = spec_from_loader(fullname, loader(fullname, filepath),
 | 
						|
                                        origin=filepath)
 | 
						|
                return spec
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def find_module(cls, fullname, path=None):
 | 
						|
        """Find module named in the registry.
 | 
						|
 | 
						|
        This method is deprecated.  Use exec_module() instead.
 | 
						|
 | 
						|
        """
 | 
						|
        spec = cls.find_spec(fullname, path)
 | 
						|
        if spec is not None:
 | 
						|
            return spec.loader
 | 
						|
        else:
 | 
						|
            return None
 | 
						|
 | 
						|
 | 
						|
class _LoaderBasics:
 | 
						|
 | 
						|
    """Base class of common code needed by both SourceLoader and
 | 
						|
    SourcelessFileLoader."""
 | 
						|
 | 
						|
    def is_package(self, fullname):
 | 
						|
        """Concrete implementation of InspectLoader.is_package by checking if
 | 
						|
        the path returned by get_filename has a filename of '__init__.py'."""
 | 
						|
        filename = _path_split(self.get_filename(fullname))[1]
 | 
						|
        filename_base = filename.rsplit('.', 1)[0]
 | 
						|
        tail_name = fullname.rpartition('.')[2]
 | 
						|
        return filename_base == '__init__' and tail_name != '__init__'
 | 
						|
 | 
						|
    def exec_module(self, module):
 | 
						|
        """Execute the module."""
 | 
						|
        code = self.get_code(module.__name__)
 | 
						|
        if code is None:
 | 
						|
            raise ImportError('cannot load module {!r} when get_code() '
 | 
						|
                              'returns None'.format(module.__name__))
 | 
						|
        _call_with_frames_removed(exec, code, module.__dict__)
 | 
						|
 | 
						|
    load_module = _load_module_shim
 | 
						|
 | 
						|
 | 
						|
class SourceLoader(_LoaderBasics):
 | 
						|
 | 
						|
    def path_mtime(self, path):
 | 
						|
        """Optional method that returns the modification time (an int) for the
 | 
						|
        specified path, where path is a str.
 | 
						|
 | 
						|
        Raises IOError when the path cannot be handled.
 | 
						|
        """
 | 
						|
        raise IOError
 | 
						|
 | 
						|
    def path_stats(self, path):
 | 
						|
        """Optional method returning a metadata dict for the specified path
 | 
						|
        to by the path (str).
 | 
						|
        Possible keys:
 | 
						|
        - 'mtime' (mandatory) is the numeric timestamp of last source
 | 
						|
          code modification;
 | 
						|
        - 'size' (optional) is the size in bytes of the source code.
 | 
						|
 | 
						|
        Implementing this method allows the loader to read bytecode files.
 | 
						|
        Raises IOError when the path cannot be handled.
 | 
						|
        """
 | 
						|
        return {'mtime': self.path_mtime(path)}
 | 
						|
 | 
						|
    def _cache_bytecode(self, source_path, cache_path, data):
 | 
						|
        """Optional method which writes data (bytes) to a file path (a str).
 | 
						|
 | 
						|
        Implementing this method allows for the writing of bytecode files.
 | 
						|
 | 
						|
        The source path is needed in order to correctly transfer permissions
 | 
						|
        """
 | 
						|
        # For backwards compatibility, we delegate to set_data()
 | 
						|
        return self.set_data(cache_path, data)
 | 
						|
 | 
						|
    def set_data(self, path, data):
 | 
						|
        """Optional method which writes data (bytes) to a file path (a str).
 | 
						|
 | 
						|
        Implementing this method allows for the writing of bytecode files.
 | 
						|
        """
 | 
						|
 | 
						|
 | 
						|
    def get_source(self, fullname):
 | 
						|
        """Concrete implementation of InspectLoader.get_source."""
 | 
						|
        path = self.get_filename(fullname)
 | 
						|
        try:
 | 
						|
            source_bytes = self.get_data(path)
 | 
						|
        except OSError as exc:
 | 
						|
            raise ImportError('source not available through get_data()',
 | 
						|
                              name=fullname) from exc
 | 
						|
        return decode_source(source_bytes)
 | 
						|
 | 
						|
    def source_to_code(self, data, path, *, _optimize=-1):
 | 
						|
        """Return the code object compiled from source.
 | 
						|
 | 
						|
        The 'data' argument can be any object type that compile() supports.
 | 
						|
        """
 | 
						|
        return _call_with_frames_removed(compile, data, path, 'exec',
 | 
						|
                                        dont_inherit=True, optimize=_optimize)
 | 
						|
 | 
						|
    def get_code(self, fullname):
 | 
						|
        """Concrete implementation of InspectLoader.get_code.
 | 
						|
 | 
						|
        Reading of bytecode requires path_stats to be implemented. To write
 | 
						|
        bytecode, set_data must also be implemented.
 | 
						|
 | 
						|
        """
 | 
						|
        source_path = self.get_filename(fullname)
 | 
						|
        source_mtime = None
 | 
						|
        try:
 | 
						|
            bytecode_path = cache_from_source(source_path)
 | 
						|
        except NotImplementedError:
 | 
						|
            bytecode_path = None
 | 
						|
        else:
 | 
						|
            try:
 | 
						|
                st = self.path_stats(source_path)
 | 
						|
            except IOError:
 | 
						|
                pass
 | 
						|
            else:
 | 
						|
                source_mtime = int(st['mtime'])
 | 
						|
                try:
 | 
						|
                    data = self.get_data(bytecode_path)
 | 
						|
                except OSError:
 | 
						|
                    pass
 | 
						|
                else:
 | 
						|
                    try:
 | 
						|
                        bytes_data = _validate_bytecode_header(data,
 | 
						|
                                source_stats=st, name=fullname,
 | 
						|
                                path=bytecode_path)
 | 
						|
                    except (ImportError, EOFError):
 | 
						|
                        pass
 | 
						|
                    else:
 | 
						|
                        _verbose_message('{} matches {}', bytecode_path,
 | 
						|
                                        source_path)
 | 
						|
                        return _compile_bytecode(bytes_data, name=fullname,
 | 
						|
                                                 bytecode_path=bytecode_path,
 | 
						|
                                                 source_path=source_path)
 | 
						|
        source_bytes = self.get_data(source_path)
 | 
						|
        code_object = self.source_to_code(source_bytes, source_path)
 | 
						|
        _verbose_message('code object from {}', source_path)
 | 
						|
        if (not sys.dont_write_bytecode and bytecode_path is not None and
 | 
						|
                source_mtime is not None):
 | 
						|
            data = _code_to_bytecode(code_object, source_mtime,
 | 
						|
                    len(source_bytes))
 | 
						|
            try:
 | 
						|
                self._cache_bytecode(source_path, bytecode_path, data)
 | 
						|
                _verbose_message('wrote {!r}', bytecode_path)
 | 
						|
            except NotImplementedError:
 | 
						|
                pass
 | 
						|
        return code_object
 | 
						|
 | 
						|
 | 
						|
class FileLoader:
 | 
						|
 | 
						|
    """Base file loader class which implements the loader protocol methods that
 | 
						|
    require file system usage."""
 | 
						|
 | 
						|
    def __init__(self, fullname, path):
 | 
						|
        """Cache the module name and the path to the file found by the
 | 
						|
        finder."""
 | 
						|
        self.name = fullname
 | 
						|
        self.path = path
 | 
						|
 | 
						|
    def __eq__(self, other):
 | 
						|
        return (self.__class__ == other.__class__ and
 | 
						|
                self.__dict__ == other.__dict__)
 | 
						|
 | 
						|
    def __hash__(self):
 | 
						|
        return hash(self.name) ^ hash(self.path)
 | 
						|
 | 
						|
    @_check_name
 | 
						|
    def load_module(self, fullname):
 | 
						|
        """Load a module from a file.
 | 
						|
 | 
						|
        This method is deprecated.  Use exec_module() instead.
 | 
						|
 | 
						|
        """
 | 
						|
        # The only reason for this method is for the name check.
 | 
						|
        # Issue #14857: Avoid the zero-argument form of super so the implementation
 | 
						|
        # of that form can be updated without breaking the frozen module
 | 
						|
        return super(FileLoader, self).load_module(fullname)
 | 
						|
 | 
						|
    @_check_name
 | 
						|
    def get_filename(self, fullname):
 | 
						|
        """Return the path to the source file as found by the finder."""
 | 
						|
        return self.path
 | 
						|
 | 
						|
    def get_data(self, path):
 | 
						|
        """Return the data from path as raw bytes."""
 | 
						|
        with _io.FileIO(path, 'r') as file:
 | 
						|
            return file.read()
 | 
						|
 | 
						|
 | 
						|
class SourceFileLoader(FileLoader, SourceLoader):
 | 
						|
 | 
						|
    """Concrete implementation of SourceLoader using the file system."""
 | 
						|
 | 
						|
    def path_stats(self, path):
 | 
						|
        """Return the metadata for the path."""
 | 
						|
        st = _path_stat(path)
 | 
						|
        return {'mtime': st.st_mtime, 'size': st.st_size}
 | 
						|
 | 
						|
    def _cache_bytecode(self, source_path, bytecode_path, data):
 | 
						|
        # Adapt between the two APIs
 | 
						|
        mode = _calc_mode(source_path)
 | 
						|
        return self.set_data(bytecode_path, data, _mode=mode)
 | 
						|
 | 
						|
    def set_data(self, path, data, *, _mode=0o666):
 | 
						|
        """Write bytes data to a file."""
 | 
						|
        parent, filename = _path_split(path)
 | 
						|
        path_parts = []
 | 
						|
        # Figure out what directories are missing.
 | 
						|
        while parent and not _path_isdir(parent):
 | 
						|
            parent, part = _path_split(parent)
 | 
						|
            path_parts.append(part)
 | 
						|
        # Create needed directories.
 | 
						|
        for part in reversed(path_parts):
 | 
						|
            parent = _path_join(parent, part)
 | 
						|
            try:
 | 
						|
                _os.mkdir(parent)
 | 
						|
            except FileExistsError:
 | 
						|
                # Probably another Python process already created the dir.
 | 
						|
                continue
 | 
						|
            except OSError as exc:
 | 
						|
                # Could be a permission error, read-only filesystem: just forget
 | 
						|
                # about writing the data.
 | 
						|
                _verbose_message('could not create {!r}: {!r}', parent, exc)
 | 
						|
                return
 | 
						|
        try:
 | 
						|
            _write_atomic(path, data, _mode)
 | 
						|
            _verbose_message('created {!r}', path)
 | 
						|
        except OSError as exc:
 | 
						|
            # Same as above: just don't write the bytecode.
 | 
						|
            _verbose_message('could not create {!r}: {!r}', path, exc)
 | 
						|
 | 
						|
 | 
						|
class SourcelessFileLoader(FileLoader, _LoaderBasics):
 | 
						|
 | 
						|
    """Loader which handles sourceless file imports."""
 | 
						|
 | 
						|
    def get_code(self, fullname):
 | 
						|
        path = self.get_filename(fullname)
 | 
						|
        data = self.get_data(path)
 | 
						|
        bytes_data = _validate_bytecode_header(data, name=fullname, path=path)
 | 
						|
        return _compile_bytecode(bytes_data, name=fullname, bytecode_path=path)
 | 
						|
 | 
						|
    def get_source(self, fullname):
 | 
						|
        """Return None as there is no source code."""
 | 
						|
        return None
 | 
						|
 | 
						|
 | 
						|
# Filled in by _setup().
 | 
						|
EXTENSION_SUFFIXES = []
 | 
						|
 | 
						|
 | 
						|
class ExtensionFileLoader:
 | 
						|
 | 
						|
    """Loader for extension modules.
 | 
						|
 | 
						|
    The constructor is designed to work with FileFinder.
 | 
						|
 | 
						|
    """
 | 
						|
 | 
						|
    def __init__(self, name, path):
 | 
						|
        self.name = name
 | 
						|
        self.path = path
 | 
						|
 | 
						|
    def __eq__(self, other):
 | 
						|
        return (self.__class__ == other.__class__ and
 | 
						|
                self.__dict__ == other.__dict__)
 | 
						|
 | 
						|
    def __hash__(self):
 | 
						|
        return hash(self.name) ^ hash(self.path)
 | 
						|
 | 
						|
    @_check_name
 | 
						|
    def load_module(self, fullname):
 | 
						|
        """Load an extension module."""
 | 
						|
        # Once an exec_module() implementation is added we can also
 | 
						|
        # add a deprecation warning here.
 | 
						|
        with _ManageReload(fullname):
 | 
						|
            module = _call_with_frames_removed(_imp.load_dynamic,
 | 
						|
                                               fullname, self.path)
 | 
						|
        _verbose_message('extension module loaded from {!r}', self.path)
 | 
						|
        is_package = self.is_package(fullname)
 | 
						|
        if is_package and not hasattr(module, '__path__'):
 | 
						|
            module.__path__ = [_path_split(self.path)[0]]
 | 
						|
        module.__loader__ = self
 | 
						|
        module.__package__ = module.__name__
 | 
						|
        if not is_package:
 | 
						|
            module.__package__ = module.__package__.rpartition('.')[0]
 | 
						|
        return module
 | 
						|
 | 
						|
    def is_package(self, fullname):
 | 
						|
        """Return True if the extension module is a package."""
 | 
						|
        file_name = _path_split(self.path)[1]
 | 
						|
        return any(file_name == '__init__' + suffix
 | 
						|
                   for suffix in EXTENSION_SUFFIXES)
 | 
						|
 | 
						|
    def get_code(self, fullname):
 | 
						|
        """Return None as an extension module cannot create a code object."""
 | 
						|
        return None
 | 
						|
 | 
						|
    def get_source(self, fullname):
 | 
						|
        """Return None as extension modules have no source code."""
 | 
						|
        return None
 | 
						|
 | 
						|
    @_check_name
 | 
						|
    def get_filename(self, fullname):
 | 
						|
        """Return the path to the source file as found by the finder."""
 | 
						|
        return self.path
 | 
						|
 | 
						|
 | 
						|
class _NamespacePath:
 | 
						|
    """Represents a namespace package's path.  It uses the module name
 | 
						|
    to find its parent module, and from there it looks up the parent's
 | 
						|
    __path__.  When this changes, the module's own path is recomputed,
 | 
						|
    using path_finder.  For top-level modules, the parent module's path
 | 
						|
    is sys.path."""
 | 
						|
 | 
						|
    def __init__(self, name, path, path_finder):
 | 
						|
        self._name = name
 | 
						|
        self._path = path
 | 
						|
        self._last_parent_path = tuple(self._get_parent_path())
 | 
						|
        self._path_finder = path_finder
 | 
						|
 | 
						|
    def _find_parent_path_names(self):
 | 
						|
        """Returns a tuple of (parent-module-name, parent-path-attr-name)"""
 | 
						|
        parent, dot, me = self._name.rpartition('.')
 | 
						|
        if dot == '':
 | 
						|
            # This is a top-level module. sys.path contains the parent path.
 | 
						|
            return 'sys', 'path'
 | 
						|
        # Not a top-level module. parent-module.__path__ contains the
 | 
						|
        #  parent path.
 | 
						|
        return parent, '__path__'
 | 
						|
 | 
						|
    def _get_parent_path(self):
 | 
						|
        parent_module_name, path_attr_name = self._find_parent_path_names()
 | 
						|
        return getattr(sys.modules[parent_module_name], path_attr_name)
 | 
						|
 | 
						|
    def _recalculate(self):
 | 
						|
        # If the parent's path has changed, recalculate _path
 | 
						|
        parent_path = tuple(self._get_parent_path()) # Make a copy
 | 
						|
        if parent_path != self._last_parent_path:
 | 
						|
            spec = self._path_finder(self._name, parent_path)
 | 
						|
            # Note that no changes are made if a loader is returned, but we
 | 
						|
            #  do remember the new parent path
 | 
						|
            if spec is not None and spec.loader is None:
 | 
						|
                if spec.submodule_search_locations:
 | 
						|
                    self._path = spec.submodule_search_locations
 | 
						|
            self._last_parent_path = parent_path     # Save the copy
 | 
						|
        return self._path
 | 
						|
 | 
						|
    def __iter__(self):
 | 
						|
        return iter(self._recalculate())
 | 
						|
 | 
						|
    def __len__(self):
 | 
						|
        return len(self._recalculate())
 | 
						|
 | 
						|
    def __repr__(self):
 | 
						|
        return '_NamespacePath({!r})'.format(self._path)
 | 
						|
 | 
						|
    def __contains__(self, item):
 | 
						|
        return item in self._recalculate()
 | 
						|
 | 
						|
    def append(self, item):
 | 
						|
        self._path.append(item)
 | 
						|
 | 
						|
 | 
						|
# We use this exclusively in init_module_attrs() for backward-compatibility.
 | 
						|
class _NamespaceLoader:
 | 
						|
    def __init__(self, name, path, path_finder):
 | 
						|
        self._path = _NamespacePath(name, path, path_finder)
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def module_repr(cls, module):
 | 
						|
        """Return repr for the module.
 | 
						|
 | 
						|
        The method is deprecated.  The import machinery does the job itself.
 | 
						|
 | 
						|
        """
 | 
						|
        return '<module {!r} (namespace)>'.format(module.__name__)
 | 
						|
 | 
						|
    def is_package(self, fullname):
 | 
						|
        return True
 | 
						|
 | 
						|
    def get_source(self, fullname):
 | 
						|
        return ''
 | 
						|
 | 
						|
    def get_code(self, fullname):
 | 
						|
        return compile('', '<string>', 'exec', dont_inherit=True)
 | 
						|
 | 
						|
    def exec_module(self, module):
 | 
						|
        pass
 | 
						|
 | 
						|
    def load_module(self, fullname):
 | 
						|
        """Load a namespace module.
 | 
						|
 | 
						|
        This method is deprecated.  Use exec_module() instead.
 | 
						|
 | 
						|
        """
 | 
						|
        # The import system never calls this method.
 | 
						|
        _verbose_message('namespace module loaded with path {!r}', self._path)
 | 
						|
        return _load_module_shim(self, fullname)
 | 
						|
 | 
						|
 | 
						|
# Finders #####################################################################
 | 
						|
 | 
						|
class PathFinder:
 | 
						|
 | 
						|
    """Meta path finder for sys.path and package __path__ attributes."""
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def invalidate_caches(cls):
 | 
						|
        """Call the invalidate_caches() method on all path entry finders
 | 
						|
        stored in sys.path_importer_caches (where implemented)."""
 | 
						|
        for finder in sys.path_importer_cache.values():
 | 
						|
            if hasattr(finder, 'invalidate_caches'):
 | 
						|
                finder.invalidate_caches()
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def _path_hooks(cls, path):
 | 
						|
        """Search sequence of hooks for a finder for 'path'.
 | 
						|
 | 
						|
        If 'hooks' is false then use sys.path_hooks.
 | 
						|
 | 
						|
        """
 | 
						|
        if not sys.path_hooks:
 | 
						|
            _warnings.warn('sys.path_hooks is empty', ImportWarning)
 | 
						|
        for hook in sys.path_hooks:
 | 
						|
            try:
 | 
						|
                return hook(path)
 | 
						|
            except ImportError:
 | 
						|
                continue
 | 
						|
        else:
 | 
						|
            return None
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def _path_importer_cache(cls, path):
 | 
						|
        """Get the finder for the path entry from sys.path_importer_cache.
 | 
						|
 | 
						|
        If the path entry is not in the cache, find the appropriate finder
 | 
						|
        and cache it. If no finder is available, store None.
 | 
						|
 | 
						|
        """
 | 
						|
        if path == '':
 | 
						|
            path = _os.getcwd()
 | 
						|
        try:
 | 
						|
            finder = sys.path_importer_cache[path]
 | 
						|
        except KeyError:
 | 
						|
            finder = cls._path_hooks(path)
 | 
						|
            sys.path_importer_cache[path] = finder
 | 
						|
        return finder
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def _legacy_get_spec(cls, fullname, finder):
 | 
						|
        # This would be a good place for a DeprecationWarning if
 | 
						|
        # we ended up going that route.
 | 
						|
        if hasattr(finder, 'find_loader'):
 | 
						|
            loader, portions = finder.find_loader(fullname)
 | 
						|
        else:
 | 
						|
            loader = finder.find_module(fullname)
 | 
						|
            portions = []
 | 
						|
        if loader is not None:
 | 
						|
            return spec_from_loader(fullname, loader)
 | 
						|
        spec = ModuleSpec(fullname, None)
 | 
						|
        spec.submodule_search_locations = portions
 | 
						|
        return spec
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def _get_spec(cls, fullname, path, target=None):
 | 
						|
        """Find the loader or namespace_path for this module/package name."""
 | 
						|
        # If this ends up being a namespace package, namespace_path is
 | 
						|
        #  the list of paths that will become its __path__
 | 
						|
        namespace_path = []
 | 
						|
        for entry in path:
 | 
						|
            if not isinstance(entry, (str, bytes)):
 | 
						|
                continue
 | 
						|
            finder = cls._path_importer_cache(entry)
 | 
						|
            if finder is not None:
 | 
						|
                if hasattr(finder, 'find_spec'):
 | 
						|
                    spec = finder.find_spec(fullname, target)
 | 
						|
                else:
 | 
						|
                    spec = cls._legacy_get_spec(fullname, finder)
 | 
						|
                if spec is None:
 | 
						|
                    continue
 | 
						|
                if spec.loader is not None:
 | 
						|
                    return spec
 | 
						|
                portions = spec.submodule_search_locations
 | 
						|
                if portions is None:
 | 
						|
                    raise ImportError('spec missing loader')
 | 
						|
                # This is possibly part of a namespace package.
 | 
						|
                #  Remember these path entries (if any) for when we
 | 
						|
                #  create a namespace package, and continue iterating
 | 
						|
                #  on path.
 | 
						|
                namespace_path.extend(portions)
 | 
						|
        else:
 | 
						|
            spec = ModuleSpec(fullname, None)
 | 
						|
            spec.submodule_search_locations = namespace_path
 | 
						|
            return spec
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def find_spec(cls, fullname, path=None, target=None):
 | 
						|
        """find the module on sys.path or 'path' based on sys.path_hooks and
 | 
						|
        sys.path_importer_cache."""
 | 
						|
        if path is None:
 | 
						|
            path = sys.path
 | 
						|
        spec = cls._get_spec(fullname, path, target)
 | 
						|
        if spec is None:
 | 
						|
            return None
 | 
						|
        elif spec.loader is None:
 | 
						|
            namespace_path = spec.submodule_search_locations
 | 
						|
            if namespace_path:
 | 
						|
                # We found at least one namespace path.  Return a
 | 
						|
                #  spec which can create the namespace package.
 | 
						|
                spec.origin = 'namespace'
 | 
						|
                spec.submodule_search_locations = _NamespacePath(fullname, namespace_path, cls._get_spec)
 | 
						|
                return spec
 | 
						|
            else:
 | 
						|
                return None
 | 
						|
        else:
 | 
						|
            return spec
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def find_module(cls, fullname, path=None):
 | 
						|
        """find the module on sys.path or 'path' based on sys.path_hooks and
 | 
						|
        sys.path_importer_cache.
 | 
						|
 | 
						|
        This method is deprecated.  Use find_spec() instead.
 | 
						|
 | 
						|
        """
 | 
						|
        spec = cls.find_spec(fullname, path)
 | 
						|
        if spec is None:
 | 
						|
            return None
 | 
						|
        return spec.loader
 | 
						|
 | 
						|
 | 
						|
class FileFinder:
 | 
						|
 | 
						|
    """File-based finder.
 | 
						|
 | 
						|
    Interactions with the file system are cached for performance, being
 | 
						|
    refreshed when the directory the finder is handling has been modified.
 | 
						|
 | 
						|
    """
 | 
						|
 | 
						|
    def __init__(self, path, *loader_details):
 | 
						|
        """Initialize with the path to search on and a variable number of
 | 
						|
        2-tuples containing the loader and the file suffixes the loader
 | 
						|
        recognizes."""
 | 
						|
        loaders = []
 | 
						|
        for loader, suffixes in loader_details:
 | 
						|
            loaders.extend((suffix, loader) for suffix in suffixes)
 | 
						|
        self._loaders = loaders
 | 
						|
        # Base (directory) path
 | 
						|
        self.path = path or '.'
 | 
						|
        self._path_mtime = -1
 | 
						|
        self._path_cache = set()
 | 
						|
        self._relaxed_path_cache = set()
 | 
						|
 | 
						|
    def invalidate_caches(self):
 | 
						|
        """Invalidate the directory mtime."""
 | 
						|
        self._path_mtime = -1
 | 
						|
 | 
						|
    find_module = _find_module_shim
 | 
						|
 | 
						|
    def find_loader(self, fullname):
 | 
						|
        """Try to find a loader for the specified module, or the namespace
 | 
						|
        package portions. Returns (loader, list-of-portions).
 | 
						|
 | 
						|
        This method is deprecated.  Use find_spec() instead.
 | 
						|
 | 
						|
        """
 | 
						|
        spec = self.find_spec(fullname)
 | 
						|
        if spec is None:
 | 
						|
            return None, []
 | 
						|
        return spec.loader, spec.submodule_search_locations or []
 | 
						|
 | 
						|
    def _get_spec(self, loader_class, fullname, path, smsl, target):
 | 
						|
        loader = loader_class(fullname, path)
 | 
						|
        return spec_from_file_location(fullname, path, loader=loader,
 | 
						|
                                       submodule_search_locations=smsl)
 | 
						|
 | 
						|
    def find_spec(self, fullname, target=None):
 | 
						|
        """Try to find a loader for the specified module, or the namespace
 | 
						|
        package portions. Returns (loader, list-of-portions)."""
 | 
						|
        is_namespace = False
 | 
						|
        tail_module = fullname.rpartition('.')[2]
 | 
						|
        try:
 | 
						|
            mtime = _path_stat(self.path or _os.getcwd()).st_mtime
 | 
						|
        except OSError:
 | 
						|
            mtime = -1
 | 
						|
        if mtime != self._path_mtime:
 | 
						|
            self._fill_cache()
 | 
						|
            self._path_mtime = mtime
 | 
						|
        # tail_module keeps the original casing, for __file__ and friends
 | 
						|
        if _relax_case():
 | 
						|
            cache = self._relaxed_path_cache
 | 
						|
            cache_module = tail_module.lower()
 | 
						|
        else:
 | 
						|
            cache = self._path_cache
 | 
						|
            cache_module = tail_module
 | 
						|
        # Check if the module is the name of a directory (and thus a package).
 | 
						|
        if cache_module in cache:
 | 
						|
            base_path = _path_join(self.path, tail_module)
 | 
						|
            for suffix, loader_class in self._loaders:
 | 
						|
                init_filename = '__init__' + suffix
 | 
						|
                full_path = _path_join(base_path, init_filename)
 | 
						|
                if _path_isfile(full_path):
 | 
						|
                    return self._get_spec(loader_class, fullname, full_path, [base_path], target)
 | 
						|
            else:
 | 
						|
                # If a namespace package, return the path if we don't
 | 
						|
                #  find a module in the next section.
 | 
						|
                is_namespace = _path_isdir(base_path)
 | 
						|
        # Check for a file w/ a proper suffix exists.
 | 
						|
        for suffix, loader_class in self._loaders:
 | 
						|
            full_path = _path_join(self.path, tail_module + suffix)
 | 
						|
            _verbose_message('trying {}'.format(full_path), verbosity=2)
 | 
						|
            if cache_module + suffix in cache:
 | 
						|
                if _path_isfile(full_path):
 | 
						|
                    return self._get_spec(loader_class, fullname, full_path, None, target)
 | 
						|
        if is_namespace:
 | 
						|
            _verbose_message('possible namespace for {}'.format(base_path))
 | 
						|
            spec = ModuleSpec(fullname, None)
 | 
						|
            spec.submodule_search_locations = [base_path]
 | 
						|
            return spec
 | 
						|
        return None
 | 
						|
 | 
						|
    def _fill_cache(self):
 | 
						|
        """Fill the cache of potential modules and packages for this directory."""
 | 
						|
        path = self.path
 | 
						|
        try:
 | 
						|
            contents = _os.listdir(path or _os.getcwd())
 | 
						|
        except (FileNotFoundError, PermissionError, NotADirectoryError):
 | 
						|
            # Directory has either been removed, turned into a file, or made
 | 
						|
            # unreadable.
 | 
						|
            contents = []
 | 
						|
        # We store two cached versions, to handle runtime changes of the
 | 
						|
        # PYTHONCASEOK environment variable.
 | 
						|
        if not sys.platform.startswith('win'):
 | 
						|
            self._path_cache = set(contents)
 | 
						|
        else:
 | 
						|
            # Windows users can import modules with case-insensitive file
 | 
						|
            # suffixes (for legacy reasons). Make the suffix lowercase here
 | 
						|
            # so it's done once instead of for every import. This is safe as
 | 
						|
            # the specified suffixes to check against are always specified in a
 | 
						|
            # case-sensitive manner.
 | 
						|
            lower_suffix_contents = set()
 | 
						|
            for item in contents:
 | 
						|
                name, dot, suffix = item.partition('.')
 | 
						|
                if dot:
 | 
						|
                    new_name = '{}.{}'.format(name, suffix.lower())
 | 
						|
                else:
 | 
						|
                    new_name = name
 | 
						|
                lower_suffix_contents.add(new_name)
 | 
						|
            self._path_cache = lower_suffix_contents
 | 
						|
        if sys.platform.startswith(_CASE_INSENSITIVE_PLATFORMS):
 | 
						|
            self._relaxed_path_cache = {fn.lower() for fn in contents}
 | 
						|
 | 
						|
    @classmethod
 | 
						|
    def path_hook(cls, *loader_details):
 | 
						|
        """A class method which returns a closure to use on sys.path_hook
 | 
						|
        which will return an instance using the specified loaders and the path
 | 
						|
        called on the closure.
 | 
						|
 | 
						|
        If the path called on the closure is not a directory, ImportError is
 | 
						|
        raised.
 | 
						|
 | 
						|
        """
 | 
						|
        def path_hook_for_FileFinder(path):
 | 
						|
            """Path hook for importlib.machinery.FileFinder."""
 | 
						|
            if not _path_isdir(path):
 | 
						|
                raise ImportError('only directories are supported', path=path)
 | 
						|
            return cls(path, *loader_details)
 | 
						|
 | 
						|
        return path_hook_for_FileFinder
 | 
						|
 | 
						|
    def __repr__(self):
 | 
						|
        return 'FileFinder({!r})'.format(self.path)
 | 
						|
 | 
						|
 | 
						|
# Import itself ###############################################################
 | 
						|
 | 
						|
class _ImportLockContext:
 | 
						|
 | 
						|
    """Context manager for the import lock."""
 | 
						|
 | 
						|
    def __enter__(self):
 | 
						|
        """Acquire the import lock."""
 | 
						|
        _imp.acquire_lock()
 | 
						|
 | 
						|
    def __exit__(self, exc_type, exc_value, exc_traceback):
 | 
						|
        """Release the import lock regardless of any raised exceptions."""
 | 
						|
        _imp.release_lock()
 | 
						|
 | 
						|
 | 
						|
def _resolve_name(name, package, level):
 | 
						|
    """Resolve a relative module name to an absolute one."""
 | 
						|
    bits = package.rsplit('.', level - 1)
 | 
						|
    if len(bits) < level:
 | 
						|
        raise ValueError('attempted relative import beyond top-level package')
 | 
						|
    base = bits[0]
 | 
						|
    return '{}.{}'.format(base, name) if name else base
 | 
						|
 | 
						|
 | 
						|
def _find_spec_legacy(finder, name, path):
 | 
						|
    # This would be a good place for a DeprecationWarning if
 | 
						|
    # we ended up going that route.
 | 
						|
    loader = finder.find_module(name, path)
 | 
						|
    if loader is None:
 | 
						|
        return None
 | 
						|
    return spec_from_loader(name, loader)
 | 
						|
 | 
						|
 | 
						|
def _find_spec(name, path, target=None):
 | 
						|
    """Find a module's loader."""
 | 
						|
    if not sys.meta_path:
 | 
						|
        _warnings.warn('sys.meta_path is empty', ImportWarning)
 | 
						|
    # We check sys.modules here for the reload case.  While a passed-in
 | 
						|
    # target will usually indicate a reload there is no guarantee, whereas
 | 
						|
    # sys.modules provides one.
 | 
						|
    is_reload = name in sys.modules
 | 
						|
    for finder in sys.meta_path:
 | 
						|
        with _ImportLockContext():
 | 
						|
            try:
 | 
						|
                find_spec = finder.find_spec
 | 
						|
            except AttributeError:
 | 
						|
                spec = _find_spec_legacy(finder, name, path)
 | 
						|
                if spec is None:
 | 
						|
                    continue
 | 
						|
            else:
 | 
						|
                spec = find_spec(name, path, target)
 | 
						|
        if spec is not None:
 | 
						|
            # The parent import may have already imported this module.
 | 
						|
            if not is_reload and name in sys.modules:
 | 
						|
                module = sys.modules[name]
 | 
						|
                try:
 | 
						|
                    __spec__ = module.__spec__
 | 
						|
                except AttributeError:
 | 
						|
                    # We use the found spec since that is the one that
 | 
						|
                    # we would have used if the parent module hadn't
 | 
						|
                    # beaten us to the punch.
 | 
						|
                    return spec
 | 
						|
                else:
 | 
						|
                    if __spec__ is None:
 | 
						|
                        return spec
 | 
						|
                    else:
 | 
						|
                        return __spec__
 | 
						|
            else:
 | 
						|
                return spec
 | 
						|
    else:
 | 
						|
        return None
 | 
						|
 | 
						|
 | 
						|
def _sanity_check(name, package, level):
 | 
						|
    """Verify arguments are "sane"."""
 | 
						|
    if not isinstance(name, str):
 | 
						|
        raise TypeError('module name must be str, not {}'.format(type(name)))
 | 
						|
    if level < 0:
 | 
						|
        raise ValueError('level must be >= 0')
 | 
						|
    if package:
 | 
						|
        if not isinstance(package, str):
 | 
						|
            raise TypeError('__package__ not set to a string')
 | 
						|
        elif package not in sys.modules:
 | 
						|
            msg = ('Parent module {!r} not loaded, cannot perform relative '
 | 
						|
                   'import')
 | 
						|
            raise SystemError(msg.format(package))
 | 
						|
    if not name and level == 0:
 | 
						|
        raise ValueError('Empty module name')
 | 
						|
 | 
						|
 | 
						|
_ERR_MSG_PREFIX = 'No module named '
 | 
						|
_ERR_MSG = _ERR_MSG_PREFIX + '{!r}'
 | 
						|
 | 
						|
def _find_and_load_unlocked(name, import_):
 | 
						|
    path = None
 | 
						|
    parent = name.rpartition('.')[0]
 | 
						|
    if parent:
 | 
						|
        if parent not in sys.modules:
 | 
						|
            _call_with_frames_removed(import_, parent)
 | 
						|
        # Crazy side-effects!
 | 
						|
        if name in sys.modules:
 | 
						|
            return sys.modules[name]
 | 
						|
        parent_module = sys.modules[parent]
 | 
						|
        try:
 | 
						|
            path = parent_module.__path__
 | 
						|
        except AttributeError:
 | 
						|
            msg = (_ERR_MSG + '; {!r} is not a package').format(name, parent)
 | 
						|
            raise ImportError(msg, name=name)
 | 
						|
    spec = _find_spec(name, path)
 | 
						|
    if spec is None:
 | 
						|
        raise ImportError(_ERR_MSG.format(name), name=name)
 | 
						|
    else:
 | 
						|
        module = _SpecMethods(spec)._load_unlocked()
 | 
						|
    if parent:
 | 
						|
        # Set the module as an attribute on its parent.
 | 
						|
        parent_module = sys.modules[parent]
 | 
						|
        setattr(parent_module, name.rpartition('.')[2], module)
 | 
						|
    return module
 | 
						|
 | 
						|
 | 
						|
def _find_and_load(name, import_):
 | 
						|
    """Find and load the module, and release the import lock."""
 | 
						|
    with _ModuleLockManager(name):
 | 
						|
        return _find_and_load_unlocked(name, import_)
 | 
						|
 | 
						|
 | 
						|
def _gcd_import(name, package=None, level=0):
 | 
						|
    """Import and return the module based on its name, the package the call is
 | 
						|
    being made from, and the level adjustment.
 | 
						|
 | 
						|
    This function represents the greatest common denominator of functionality
 | 
						|
    between import_module and __import__. This includes setting __package__ if
 | 
						|
    the loader did not.
 | 
						|
 | 
						|
    """
 | 
						|
    _sanity_check(name, package, level)
 | 
						|
    if level > 0:
 | 
						|
        name = _resolve_name(name, package, level)
 | 
						|
    _imp.acquire_lock()
 | 
						|
    if name not in sys.modules:
 | 
						|
        return _find_and_load(name, _gcd_import)
 | 
						|
    module = sys.modules[name]
 | 
						|
    if module is None:
 | 
						|
        _imp.release_lock()
 | 
						|
        message = ('import of {} halted; '
 | 
						|
                   'None in sys.modules'.format(name))
 | 
						|
        raise ImportError(message, name=name)
 | 
						|
    _lock_unlock_module(name)
 | 
						|
    return module
 | 
						|
 | 
						|
def _handle_fromlist(module, fromlist, import_):
 | 
						|
    """Figure out what __import__ should return.
 | 
						|
 | 
						|
    The import_ parameter is a callable which takes the name of module to
 | 
						|
    import. It is required to decouple the function from assuming importlib's
 | 
						|
    import implementation is desired.
 | 
						|
 | 
						|
    """
 | 
						|
    # The hell that is fromlist ...
 | 
						|
    # If a package was imported, try to import stuff from fromlist.
 | 
						|
    if hasattr(module, '__path__'):
 | 
						|
        if '*' in fromlist:
 | 
						|
            fromlist = list(fromlist)
 | 
						|
            fromlist.remove('*')
 | 
						|
            if hasattr(module, '__all__'):
 | 
						|
                fromlist.extend(module.__all__)
 | 
						|
        for x in fromlist:
 | 
						|
            if not hasattr(module, x):
 | 
						|
                from_name = '{}.{}'.format(module.__name__, x)
 | 
						|
                try:
 | 
						|
                    _call_with_frames_removed(import_, from_name)
 | 
						|
                except ImportError as exc:
 | 
						|
                    # Backwards-compatibility dictates we ignore failed
 | 
						|
                    # imports triggered by fromlist for modules that don't
 | 
						|
                    # exist.
 | 
						|
                    if str(exc).startswith(_ERR_MSG_PREFIX):
 | 
						|
                        if exc.name == from_name:
 | 
						|
                            continue
 | 
						|
                    raise
 | 
						|
    return module
 | 
						|
 | 
						|
 | 
						|
def _calc___package__(globals):
 | 
						|
    """Calculate what __package__ should be.
 | 
						|
 | 
						|
    __package__ is not guaranteed to be defined or could be set to None
 | 
						|
    to represent that its proper value is unknown.
 | 
						|
 | 
						|
    """
 | 
						|
    package = globals.get('__package__')
 | 
						|
    if package is None:
 | 
						|
        package = globals['__name__']
 | 
						|
        if '__path__' not in globals:
 | 
						|
            package = package.rpartition('.')[0]
 | 
						|
    return package
 | 
						|
 | 
						|
 | 
						|
def _get_supported_file_loaders():
 | 
						|
    """Returns a list of file-based module loaders.
 | 
						|
 | 
						|
    Each item is a tuple (loader, suffixes).
 | 
						|
    """
 | 
						|
    extensions = ExtensionFileLoader, _imp.extension_suffixes()
 | 
						|
    source = SourceFileLoader, SOURCE_SUFFIXES
 | 
						|
    bytecode = SourcelessFileLoader, BYTECODE_SUFFIXES
 | 
						|
    return [extensions, source, bytecode]
 | 
						|
 | 
						|
 | 
						|
def __import__(name, globals=None, locals=None, fromlist=(), level=0):
 | 
						|
    """Import a module.
 | 
						|
 | 
						|
    The 'globals' argument is used to infer where the import is occuring from
 | 
						|
    to handle relative imports. The 'locals' argument is ignored. The
 | 
						|
    'fromlist' argument specifies what should exist as attributes on the module
 | 
						|
    being imported (e.g. ``from module import <fromlist>``).  The 'level'
 | 
						|
    argument represents the package location to import from in a relative
 | 
						|
    import (e.g. ``from ..pkg import mod`` would have a 'level' of 2).
 | 
						|
 | 
						|
    """
 | 
						|
    if level == 0:
 | 
						|
        module = _gcd_import(name)
 | 
						|
    else:
 | 
						|
        globals_ = globals if globals is not None else {}
 | 
						|
        package = _calc___package__(globals_)
 | 
						|
        module = _gcd_import(name, package, level)
 | 
						|
    if not fromlist:
 | 
						|
        # Return up to the first dot in 'name'. This is complicated by the fact
 | 
						|
        # that 'name' may be relative.
 | 
						|
        if level == 0:
 | 
						|
            return _gcd_import(name.partition('.')[0])
 | 
						|
        elif not name:
 | 
						|
            return module
 | 
						|
        else:
 | 
						|
            # Figure out where to slice the module's name up to the first dot
 | 
						|
            # in 'name'.
 | 
						|
            cut_off = len(name) - len(name.partition('.')[0])
 | 
						|
            # Slice end needs to be positive to alleviate need to special-case
 | 
						|
            # when ``'.' not in name``.
 | 
						|
            return sys.modules[module.__name__[:len(module.__name__)-cut_off]]
 | 
						|
    else:
 | 
						|
        return _handle_fromlist(module, fromlist, _gcd_import)
 | 
						|
 | 
						|
 | 
						|
def _builtin_from_name(name):
 | 
						|
    spec = BuiltinImporter.find_spec(name)
 | 
						|
    if spec is None:
 | 
						|
        raise ImportError('no built-in module named ' + name)
 | 
						|
    methods = _SpecMethods(spec)
 | 
						|
    return methods._load_unlocked()
 | 
						|
 | 
						|
 | 
						|
def _setup(sys_module, _imp_module):
 | 
						|
    """Setup importlib by importing needed built-in modules and injecting them
 | 
						|
    into the global namespace.
 | 
						|
 | 
						|
    As sys is needed for sys.modules access and _imp is needed to load built-in
 | 
						|
    modules, those two modules must be explicitly passed in.
 | 
						|
 | 
						|
    """
 | 
						|
    global _imp, sys, BYTECODE_SUFFIXES
 | 
						|
    _imp = _imp_module
 | 
						|
    sys = sys_module
 | 
						|
 | 
						|
    if sys.flags.optimize:
 | 
						|
        BYTECODE_SUFFIXES = OPTIMIZED_BYTECODE_SUFFIXES
 | 
						|
    else:
 | 
						|
        BYTECODE_SUFFIXES = DEBUG_BYTECODE_SUFFIXES
 | 
						|
 | 
						|
    # Set up the spec for existing builtin/frozen modules.
 | 
						|
    module_type = type(sys)
 | 
						|
    for name, module in sys.modules.items():
 | 
						|
        if isinstance(module, module_type):
 | 
						|
            if name in sys.builtin_module_names:
 | 
						|
                loader = BuiltinImporter
 | 
						|
            elif _imp.is_frozen(name):
 | 
						|
                loader = FrozenImporter
 | 
						|
            else:
 | 
						|
                continue
 | 
						|
            spec = _spec_from_module(module, loader)
 | 
						|
            methods = _SpecMethods(spec)
 | 
						|
            methods.init_module_attrs(module)
 | 
						|
 | 
						|
    # Directly load built-in modules needed during bootstrap.
 | 
						|
    self_module = sys.modules[__name__]
 | 
						|
    for builtin_name in ('_io', '_warnings', 'builtins', 'marshal'):
 | 
						|
        if builtin_name not in sys.modules:
 | 
						|
            builtin_module = _builtin_from_name(builtin_name)
 | 
						|
        else:
 | 
						|
            builtin_module = sys.modules[builtin_name]
 | 
						|
        setattr(self_module, builtin_name, builtin_module)
 | 
						|
 | 
						|
    # Directly load the os module (needed during bootstrap).
 | 
						|
    os_details = ('posix', ['/']), ('nt', ['\\', '/'])
 | 
						|
    for builtin_os, path_separators in os_details:
 | 
						|
        # Assumption made in _path_join()
 | 
						|
        assert all(len(sep) == 1 for sep in path_separators)
 | 
						|
        path_sep = path_separators[0]
 | 
						|
        if builtin_os in sys.modules:
 | 
						|
            os_module = sys.modules[builtin_os]
 | 
						|
            break
 | 
						|
        else:
 | 
						|
            try:
 | 
						|
                os_module = _builtin_from_name(builtin_os)
 | 
						|
                break
 | 
						|
            except ImportError:
 | 
						|
                continue
 | 
						|
    else:
 | 
						|
        raise ImportError('importlib requires posix or nt')
 | 
						|
    setattr(self_module, '_os', os_module)
 | 
						|
    setattr(self_module, 'path_sep', path_sep)
 | 
						|
    setattr(self_module, 'path_separators', ''.join(path_separators))
 | 
						|
 | 
						|
    # Directly load the _thread module (needed during bootstrap).
 | 
						|
    try:
 | 
						|
        thread_module = _builtin_from_name('_thread')
 | 
						|
    except ImportError:
 | 
						|
        # Python was built without threads
 | 
						|
        thread_module = None
 | 
						|
    setattr(self_module, '_thread', thread_module)
 | 
						|
 | 
						|
    # Directly load the _weakref module (needed during bootstrap).
 | 
						|
    weakref_module = _builtin_from_name('_weakref')
 | 
						|
    setattr(self_module, '_weakref', weakref_module)
 | 
						|
 | 
						|
    # Directly load the winreg module (needed during bootstrap).
 | 
						|
    if builtin_os == 'nt':
 | 
						|
        winreg_module = _builtin_from_name('winreg')
 | 
						|
        setattr(self_module, '_winreg', winreg_module)
 | 
						|
 | 
						|
    # Constants
 | 
						|
    setattr(self_module, '_relax_case', _make_relax_case())
 | 
						|
    EXTENSION_SUFFIXES.extend(_imp.extension_suffixes())
 | 
						|
    if builtin_os == 'nt':
 | 
						|
        SOURCE_SUFFIXES.append('.pyw')
 | 
						|
        if '_d.pyd' in EXTENSION_SUFFIXES:
 | 
						|
            WindowsRegistryFinder.DEBUG_BUILD = True
 | 
						|
 | 
						|
 | 
						|
def _install(sys_module, _imp_module):
 | 
						|
    """Install importlib as the implementation of import."""
 | 
						|
    _setup(sys_module, _imp_module)
 | 
						|
    supported_loaders = _get_supported_file_loaders()
 | 
						|
    sys.path_hooks.extend([FileFinder.path_hook(*supported_loaders)])
 | 
						|
    sys.meta_path.append(BuiltinImporter)
 | 
						|
    sys.meta_path.append(FrozenImporter)
 | 
						|
    if _os.__name__ == 'nt':
 | 
						|
        sys.meta_path.append(WindowsRegistryFinder)
 | 
						|
    sys.meta_path.append(PathFinder)
 |