[3.12] GH-119054: Add "Reading and writing files" section to pathlib docs (GH-119524) (#119955)

Add a dedicated subsection for `open()`, `read_text()`, `read_bytes()`,
`write_text()` and `write_bytes()`.

(cherry picked from commit bd6d4ed645)

Doc/library/pathlib.rst

@@ -959,6 +959,87 @@ Querying file type and status
    .. versionadded:: 3.5
 
 
+Reading and writing files
+^^^^^^^^^^^^^^^^^^^^^^^^^
+
+
+.. method:: Path.open(mode='r', buffering=-1, encoding=None, errors=None, newline=None)
+
+   Open the file pointed to by the path, like the built-in :func:`open`
+   function does::
+
+      >>> p = Path('setup.py')
+      >>> with p.open() as f:
+      ...     f.readline()
+      ...
+      '#!/usr/bin/env python3\n'
+
+
+.. method:: Path.read_text(encoding=None, errors=None)
+
+   Return the decoded contents of the pointed-to file as a string::
+
+      >>> p = Path('my_text_file')
+      >>> p.write_text('Text file contents')
+      18
+      >>> p.read_text()
+      'Text file contents'
+
+   The file is opened and then closed. The optional parameters have the same
+   meaning as in :func:`open`.
+
+   .. versionadded:: 3.5
+
+
+.. method:: Path.read_bytes()
+
+   Return the binary contents of the pointed-to file as a bytes object::
+
+      >>> p = Path('my_binary_file')
+      >>> p.write_bytes(b'Binary file contents')
+      20
+      >>> p.read_bytes()
+      b'Binary file contents'
+
+   .. versionadded:: 3.5
+
+
+.. method:: Path.write_text(data, encoding=None, errors=None, newline=None)
+
+   Open the file pointed to in text mode, write *data* to it, and close the
+   file::
+
+      >>> p = Path('my_text_file')
+      >>> p.write_text('Text file contents')
+      18
+      >>> p.read_text()
+      'Text file contents'
+
+   An existing file of the same name is overwritten. The optional parameters
+   have the same meaning as in :func:`open`.
+
+   .. versionadded:: 3.5
+
+   .. versionchanged:: 3.10
+      The *newline* parameter was added.
+
+
+.. method:: Path.write_bytes(data)
+
+   Open the file pointed to in bytes mode, write *data* to it, and close the
+   file::
+
+      >>> p = Path('my_binary_file')
+      >>> p.write_bytes(b'Binary file contents')
+      20
+      >>> p.read_bytes()
+      b'Binary file contents'
+
+   An existing file of the same name is overwritten.
+
+   .. versionadded:: 3.5
+
+
 Other methods
 ^^^^^^^^^^^^^
 
@@ -1222,53 +1303,12 @@ example because the path doesn't exist).
       The *exist_ok* parameter was added.
 
 
-.. method:: Path.open(mode='r', buffering=-1, encoding=None, errors=None, newline=None)
-
-   Open the file pointed to by the path, like the built-in :func:`open`
-   function does::
-
-      >>> p = Path('setup.py')
-      >>> with p.open() as f:
-      ...     f.readline()
-      ...
-      '#!/usr/bin/env python3\n'
-
-
 .. method:: Path.owner()
 
    Return the name of the user owning the file.  :exc:`KeyError` is raised
    if the file's uid isn't found in the system database.
 
 
-.. method:: Path.read_bytes()
-
-   Return the binary contents of the pointed-to file as a bytes object::
-
-      >>> p = Path('my_binary_file')
-      >>> p.write_bytes(b'Binary file contents')
-      20
-      >>> p.read_bytes()
-      b'Binary file contents'
-
-   .. versionadded:: 3.5
-
-
-.. method:: Path.read_text(encoding=None, errors=None)
-
-   Return the decoded contents of the pointed-to file as a string::
-
-      >>> p = Path('my_text_file')
-      >>> p.write_text('Text file contents')
-      18
-      >>> p.read_text()
-      'Text file contents'
-
-   The file is opened and then closed. The optional parameters have the same
-   meaning as in :func:`open`.
-
-   .. versionadded:: 3.5
-
-
 .. method:: Path.readlink()
 
    Return the path to which the symbolic link points (as returned by
@@ -1454,41 +1494,6 @@ example because the path doesn't exist).
       The *missing_ok* parameter was added.
 
 
-.. method:: Path.write_bytes(data)
-
-   Open the file pointed to in bytes mode, write *data* to it, and close the
-   file::
-
-      >>> p = Path('my_binary_file')
-      >>> p.write_bytes(b'Binary file contents')
-      20
-      >>> p.read_bytes()
-      b'Binary file contents'
-
-   An existing file of the same name is overwritten.
-
-   .. versionadded:: 3.5
-
-
-.. method:: Path.write_text(data, encoding=None, errors=None, newline=None)
-
-   Open the file pointed to in text mode, write *data* to it, and close the
-   file::
-
-      >>> p = Path('my_text_file')
-      >>> p.write_text('Text file contents')
-      18
-      >>> p.read_text()
-      'Text file contents'
-
-   An existing file of the same name is overwritten. The optional parameters
-   have the same meaning as in :func:`open`.
-
-   .. versionadded:: 3.5
-
-   .. versionchanged:: 3.10
-      The *newline* parameter was added.
-
 Correspondence to tools in the :mod:`os` module
 -----------------------------------------------