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svn+ssh://pythondev@svn.python.org/python/trunk ........ r58745 | georg.brandl | 2007-11-01 10:19:33 -0700 (Thu, 01 Nov 2007) | 2 lines #1364: os.lstat is available on Windows too, as an alias to os.stat. ........ r58750 | christian.heimes | 2007-11-01 12:48:10 -0700 (Thu, 01 Nov 2007) | 1 line Backport of import tests for bug http://bugs.python.org/issue1293 and bug http://bugs.python.org/issue1342 ........ r58751 | christian.heimes | 2007-11-01 13:11:06 -0700 (Thu, 01 Nov 2007) | 1 line Removed non ASCII text from test as requested by Guido. Sorry :/ ........ r58753 | georg.brandl | 2007-11-01 13:37:02 -0700 (Thu, 01 Nov 2007) | 2 lines Fix markup glitch. ........ r58757 | gregory.p.smith | 2007-11-01 14:08:14 -0700 (Thu, 01 Nov 2007) | 4 lines Fix bug introduced in revision 58385. Database keys could no longer have NULL bytes in them. Replace the errant strdup with a malloc+memcpy. Adds a unit test for the correct behavior. ........ r58758 | gregory.p.smith | 2007-11-01 14:15:36 -0700 (Thu, 01 Nov 2007) | 3 lines Undo revision 58533 58534 fixes. Those were a workaround for a problem introduced by 58385. ........ r58759 | gregory.p.smith | 2007-11-01 14:17:47 -0700 (Thu, 01 Nov 2007) | 2 lines false "fix" undone as correct problem was found and fixed. ........ r58765 | mark.summerfield | 2007-11-02 01:24:59 -0700 (Fri, 02 Nov 2007) | 3 lines Added more file-handling related cross-references. ........ r58766 | nick.coghlan | 2007-11-02 03:09:12 -0700 (Fri, 02 Nov 2007) | 1 line Fix for bug 1705170 - contextmanager swallowing StopIteration (2.5 backport candidate) ........ r58784 | thomas.heller | 2007-11-02 12:10:24 -0700 (Fri, 02 Nov 2007) | 4 lines Issue #1292: On alpha, arm, ppc, and s390 linux systems the --with-system-ffi configure option defaults to "yes" because the bundled libffi sources are too old. ........ r58785 | thomas.heller | 2007-11-02 12:11:23 -0700 (Fri, 02 Nov 2007) | 1 line Enable the full ctypes c_longdouble tests again. ........ r58796 | georg.brandl | 2007-11-02 13:06:17 -0700 (Fri, 02 Nov 2007) | 4 lines Make "hashable" a glossary entry and clarify docs on __cmp__, __eq__ and __hash__. I hope the concept of hashability is better understandable now. Thanks to Tim Hatch for pointing out the flaws here. ........
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20 changed files with 139 additions and 85 deletions
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@ -260,7 +260,7 @@ compared to an object of a different type, :exc:`TypeError` is raised unless the
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comparison is ``==`` or ``!=``. The latter cases return :const:`False` or
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:const:`True`, respectively.
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:class:`timedelta` objects are hashable (usable as dictionary keys), support
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:class:`timedelta` objects are :term:`hashable` (usable as dictionary keys), support
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efficient pickling, and in Boolean contexts, a :class:`timedelta` object is
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considered to be true if and only if it isn't equal to ``timedelta(0)``.
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@ -18,7 +18,7 @@ diffs. For comparing directories and files, see also, the :mod:`filecmp` module.
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.. class:: SequenceMatcher
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This is a flexible class for comparing pairs of sequences of any type, so long
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as the sequence elements are hashable. The basic algorithm predates, and is a
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as the sequence elements are :term:`hashable`. The basic algorithm predates, and is a
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little fancier than, an algorithm published in the late 1980's by Ratcliff and
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Obershelp under the hyperbolic name "gestalt pattern matching." The idea is to
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find the longest contiguous matching subsequence that contains no "junk"
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@ -305,7 +305,7 @@ The :class:`SequenceMatcher` class has this constructor:
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on blanks or hard tabs.
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The optional arguments *a* and *b* are sequences to be compared; both default to
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empty strings. The elements of both sequences must be hashable.
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empty strings. The elements of both sequences must be :term:`hashable`.
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:class:`SequenceMatcher` objects have the following methods:
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@ -747,9 +747,9 @@ available. They are listed here in alphabetical order.
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value of ``None`` (if no newlines have been seen yet), ``'\n'``,
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``'\r'``, ``'\r\n'``, or a tuple containing all the newline types seen.
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See also the :mod:`fileinput` module, the file-related functions in the
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:mod:`os` module, and the :mod:`os.path` module.
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Python provides many file handling modules including
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:mod:`fileinput`, :mod:`os`, :mod:`os.path`, :mod:`tempfile`, and
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:mod:`shutil`.
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.. function:: ord(c)
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@ -11,7 +11,9 @@ functionality than importing a operating system dependent built-in module like
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:mod:`posix` or :mod:`nt`. If you just want to read or write a file see
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:func:`open`, if you want to manipulate paths, see the :mod:`os.path`
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module, and if you want to read all the lines in all the files on the
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command line see the :mod:`fileinput` module.
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command line see the :mod:`fileinput` module. For creating temporary
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files and directories see the :mod:`tempfile` module, and for high-level
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file and directory handling see the :mod:`shutil` module.
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This module searches for an operating system dependent built-in module like
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:mod:`mac` or :mod:`posix` and exports the same functions and data as found
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@ -800,8 +802,9 @@ Files and Directories
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.. function:: lstat(path)
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Like :func:`stat`, but do not follow symbolic links. Availability: Macintosh,
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Unix.
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Like :func:`stat`, but do not follow symbolic links. This is an alias for
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:func:`stat` on platforms that do not support symbolic links, such as
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Windows.
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.. function:: mkfifo(path[, mode])
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@ -852,6 +855,9 @@ Files and Directories
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``0777`` (octal). On some systems, *mode* is ignored. Where it is used, the
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current umask value is first masked out. Availability: Macintosh, Unix, Windows.
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It is also possible to create temporary directories; see the
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:mod:`tempfile` module's :func:`tempfile.mkdtemp` function.
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.. function:: makedirs(path[, mode])
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@ -54,7 +54,7 @@ Bookkeeping functions:
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.. function:: seed([x])
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Initialize the basic random number generator. Optional argument *x* can be any
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hashable object. If *x* is omitted or ``None``, current system time is used;
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:term:`hashable` object. If *x* is omitted or ``None``, current system time is used;
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current system time is also used to initialize the generator when the module is
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first imported. If randomness sources are provided by the operating system,
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they are used instead of the system time (see the :func:`os.urandom` function
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@ -140,7 +140,7 @@ Functions for sequences:
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(the sample) to be partitioned into grand prize and second place winners (the
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subslices).
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Members of the population need not be hashable or unique. If the population
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Members of the population need not be :term:`hashable` or unique. If the population
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contains repeats, then each occurrence is a possible selection in the sample.
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To choose a sample from a range of integers, use an :func:`range` object as an
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@ -15,7 +15,8 @@
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The :mod:`shutil` module offers a number of high-level operations on files and
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collections of files. In particular, functions are provided which support file
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copying and removal.
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copying and removal. For operations on individual files, see also the
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:mod:`os` module.
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.. warning::
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@ -874,7 +874,7 @@ functions based on regular expressions.
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specified, then there is no limit on the number of splits (all possible
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splits are made).
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If *sep is given, consecutive delimiters are not grouped together and are
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If *sep* is given, consecutive delimiters are not grouped together and are
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deemed to delimit empty strings (for example, ``'1,,2'.split(',')`` returns
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``['1', '', '2']``). The *sep* argument may consist of multiple characters
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(for example, ``'1<>2<>3'.split('<>')`` returns ``['1', '2', '3']``).
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@ -1371,7 +1371,7 @@ Set Types --- :class:`set`, :class:`frozenset`
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.. index:: object: set
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A :dfn:`set` object is an unordered collection of distinct hashable objects.
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A :dfn:`set` object is an unordered collection of distinct :term:`hashable` objects.
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Common uses include membership testing, removing duplicates from a sequence, and
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computing mathematical operations such as intersection, union, difference, and
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symmetric difference.
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@ -1387,7 +1387,7 @@ There are currently two builtin set types, :class:`set` and :class:`frozenset`.
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The :class:`set` type is mutable --- the contents can be changed using methods
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like :meth:`add` and :meth:`remove`. Since it is mutable, it has no hash value
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and cannot be used as either a dictionary key or as an element of another set.
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The :class:`frozenset` type is immutable and hashable --- its contents cannot be
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The :class:`frozenset` type is immutable and :term:`hashable` --- its contents cannot be
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altered after it is created; it can therefore be used as a dictionary key or as
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an element of another set.
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@ -1487,8 +1487,7 @@ or ``a>b``. Accordingly, sets do not implement the :meth:`__cmp__` method.
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Since sets only define partial ordering (subset relationships), the output of
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the :meth:`list.sort` method is undefined for lists of sets.
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Set elements are like dictionary keys; they need to define both :meth:`__hash__`
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and :meth:`__eq__` methods.
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Set elements, like dictionary keys, must be :term:`hashable`.
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Binary operations that mix :class:`set` instances with :class:`frozenset` return
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the type of the first operand. For example: ``frozenset('ab') | set('bc')``
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statement: del
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builtin: len
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A :dfn:`mapping` object maps immutable values to arbitrary objects. Mappings
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are mutable objects. There is currently only one standard mapping type, the
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:dfn:`dictionary`.
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(For other containers see the built in :class:`list`,
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:class:`set`, and :class:`tuple` classes, and the :mod:`collections`
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module.)
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A :dfn:`mapping` object maps :term:`hashable` values to arbitrary objects.
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Mappings are mutable objects. There is currently only one standard mapping
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type, the :dfn:`dictionary`. (For other containers see the built in
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:class:`list`, :class:`set`, and :class:`tuple` classes, and the
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:mod:`collections` module.)
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A dictionary's keys are *almost* arbitrary values. Only values containing
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lists, dictionaries or other mutable types (that are compared by value rather
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than by object identity) may not be used as keys. Numeric types used for keys
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obey the normal rules for numeric comparison: if two numbers compare equal (such
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as ``1`` and ``1.0``) then they can be used interchangeably to index the same
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dictionary entry. (Note however, that since computers store floating-point
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numbers as approximations it is usually unwise to use them as dictionary keys.)
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A dictionary's keys are *almost* arbitrary values. Values that are not
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:term:`hashable`, that is, values containing lists, dictionaries or other
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mutable types (that are compared by value rather than by object identity) may
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not be used as keys. Numeric types used for keys obey the normal rules for
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numeric comparison: if two numbers compare equal (such as ``1`` and ``1.0``)
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then they can be used interchangeably to index the same dictionary entry. (Note
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however, that since computers store floating-point numbers as approximations it
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is usually unwise to use them as dictionary keys.)
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Dictionaries can be created by placing a comma-separated list of ``key: value``
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pairs within braces, for example: ``{'jack': 4098, 'sjoerd': 4127}`` or ``{4098:
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@ -1821,7 +1820,10 @@ created with the built-in :func:`file` and (more usually) :func:`open`
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constructors described in the :ref:`built-in-funcs` section. [#]_ File
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objects are also returned by some other built-in functions and methods,
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such as :func:`os.popen` and :func:`os.fdopen` and the :meth:`makefile`
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method of socket objects.
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method of socket objects. Temporary files can be created using the
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:mod:`tempfile` module, and high-level file operations such as copying,
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moving, and deleting files and directories can be achieved with the
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:mod:`shutil` module.
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When a file operation fails for an I/O-related reason, the exception
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:exc:`IOError` is raised. This includes situations where the operation is not
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@ -85,7 +85,7 @@ Extension types can easily be made to support weak references; see
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but cannot be propagated; they are handled in exactly the same way as exceptions
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raised from an object's :meth:`__del__` method.
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Weak references are hashable if the *object* is hashable. They will maintain
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Weak references are :term:`hashable` if the *object* is hashable. They will maintain
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their hash value even after the *object* was deleted. If :func:`hash` is called
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the first time only after the *object* was deleted, the call will raise
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:exc:`TypeError`.
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the proxy in most contexts instead of requiring the explicit dereferencing used
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with weak reference objects. The returned object will have a type of either
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``ProxyType`` or ``CallableProxyType``, depending on whether *object* is
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callable. Proxy objects are not hashable regardless of the referent; this
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callable. Proxy objects are not :term:`hashable` regardless of the referent; this
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avoids a number of problems related to their fundamentally mutable nature, and
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prevent their use as dictionary keys. *callback* is the same as the parameter
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of the same name to the :func:`ref` function.
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