sthagen · sthagen · May 15, 2021 · May 13, 2021 · May 13, 2021 · May 13, 2021
diff --git a/Doc/c-api/stable.rst b/Doc/c-api/stable.rst
@@ -41,22 +41,22 @@ embedding Python.)
 
 .. c:macro:: Py_LIMITED_API
 
-   Define this macro ``Py_LIMITED_API`` before including ``Python.h`` to
-   opt in to only use the Limited API.
-
-   Defining ``Py_LIMITED_API`` to ``3`` will limit the available API so that
-   the extension will work without recompilation with all Python 3.x releases
-   (x>=2) on the particular  :ref:`platform <stable-abi-platform>`.
-
-   Defining ``Py_LIMITED_API`` to a value of :c:data:`PY_VERSION_HEX` will
-   limit the available API so that the extension will work without
-   recompilation with all Python 3 releases from the specified one.
-   This will allow using additional API introduced up to this version,
-   but the extension will lose compatibility with earlier Python versions.
+   Define this macro before including ``Python.h`` to opt in to only use
+   the Limited API, and to select the Limited API version.
+
+   Define ``Py_LIMITED_API`` to the value of :c:data:`PY_VERSION_HEX`
+   corresponding to the lowest Python version your extension supports.
+   The extension will work without recompilation with all Python 3 releases
+   from the specified one onward, and can use Limited API introduced up to that
+   version.
+
    Rather than using the ``PY_VERSION_HEX`` macro directly, hardcode a minimum
    minor version (e.g. ``0x030A0000`` for Python 3.10) for stability when
    compiling with future Python versions.
 
+   You can also define ``Py_LIMITED_API`` to ``3``. This works the same as
+   ``0x03020000`` (Python 3.2, the version that introduced Limited API).
+
 On Windows, extensions that use the Stable ABI should be linked against
 ``python3.dll`` rather than a version-specific library such as
 ``python39.dll``.

diff --git a/Doc/library/asyncio-protocol.rst b/Doc/library/asyncio-protocol.rst
@@ -683,7 +683,7 @@ factories passed to the :meth:`loop.create_datagram_endpoint` method.
 Subprocess Protocols
 --------------------
 
-Datagram Protocol instances should be constructed by protocol
+Subprocess Protocol instances should be constructed by protocol
 factories passed to the :meth:`loop.subprocess_exec` and
 :meth:`loop.subprocess_shell` methods.
 

diff --git a/Doc/library/asyncio-task.rst b/Doc/library/asyncio-task.rst
@@ -358,32 +358,35 @@ Running Tasks Concurrently
       async def factorial(name, number):
           f = 1
           for i in range(2, number + 1):
-              print(f"Task {name}: Compute factorial({i})...")
+              print(f"Task {name}: Compute factorial({number}), currently i={i}...")
               await asyncio.sleep(1)
               f *= i
           print(f"Task {name}: factorial({number}) = {f}")
+          return f
 
       async def main():
           # Schedule three calls *concurrently*:
-          await asyncio.gather(
+          L = await asyncio.gather(
               factorial("A", 2),
               factorial("B", 3),
               factorial("C", 4),
           )
+          print(L)
 
       asyncio.run(main())
 
       # Expected output:
       #
-      #     Task A: Compute factorial(2)...
-      #     Task B: Compute factorial(2)...
-      #     Task C: Compute factorial(2)...
+      #     Task A: Compute factorial(2), currently i=2...
+      #     Task B: Compute factorial(3), currently i=2...
+      #     Task C: Compute factorial(4), currently i=2...
       #     Task A: factorial(2) = 2
-      #     Task B: Compute factorial(3)...
-      #     Task C: Compute factorial(3)...
+      #     Task B: Compute factorial(3), currently i=3...
+      #     Task C: Compute factorial(4), currently i=3...
       #     Task B: factorial(3) = 6
-      #     Task C: Compute factorial(4)...
+      #     Task C: Compute factorial(4), currently i=4...
       #     Task C: factorial(4) = 24
+      #     [2, 6, 24]
 
    .. note::
       If *return_exceptions* is False, cancelling gather() after it

diff --git a/Doc/library/cgi.rst b/Doc/library/cgi.rst
@@ -316,7 +316,7 @@ algorithms implemented in this module in other circumstances.
 .. function:: test()
 
    Robust test CGI script, usable as main program. Writes minimal HTTP headers and
-   formats all information provided to the script in HTML form.
+   formats all information provided to the script in HTML format.
 
 
 .. function:: print_environ()
@@ -346,8 +346,8 @@ Caring about security
 
 .. index:: pair: CGI; security
 
-There's one important rule: if you invoke an external program (via the
-:func:`os.system` or :func:`os.popen` functions. or others with similar
+There's one important rule: if you invoke an external program (via
+:func:`os.system`, :func:`os.popen` or other functions with similar
 functionality), make very sure you don't pass arbitrary strings received from
 the client to the shell.  This is a well-known security hole whereby clever
 hackers anywhere on the Web can exploit a gullible CGI script to invoke
@@ -424,7 +424,7 @@ above on installing your CGI script carefully can save you a lot of time.  If
 you wonder whether you have understood the installation procedure correctly, try
 installing a copy of this module file (:file:`cgi.py`) as a CGI script.  When
 invoked as a script, the file will dump its environment and the contents of the
-form in HTML form. Give it the right mode etc, and send it a request.  If it's
+form in HTML format. Give it the right mode etc., and send it a request.  If it's
 installed in the standard :file:`cgi-bin` directory, it should be possible to
 send it a request by entering a URL into your browser of the form:
 

diff --git a/Doc/library/enum.rst b/Doc/library/enum.rst
@@ -575,6 +575,8 @@ Data Types
          >>> KeepFlag(2**2 + 2**4)
          KeepFlag.BLUE|0x10
 
+.. versionadded:: 3.10  ``FlagBoundary``
+
 
 Utilites and Decorators
 -----------------------
@@ -598,6 +600,7 @@ Utilites and Decorators
    also injects the members, and their aliases, into the the global namespace
    they were defined in.
 
+.. versionadded:: 3.10
 
 .. decorator:: property
 
@@ -610,6 +613,8 @@ Utilites and Decorators
              *Enum* class, and *Enum* subclasses can define members with the
              names ``value`` and ``name``.
 
+.. versionadded:: 3.10
+
 .. decorator:: unique
 
    A :keyword:`class` decorator specifically for enumerations.  It searches an

diff --git a/Doc/library/numbers.rst b/Doc/library/numbers.rst
@@ -27,8 +27,8 @@ The numeric tower
    Subclasses of this type describe complex numbers and include the operations
    that work on the built-in :class:`complex` type. These are: conversions to
    :class:`complex` and :class:`bool`, :attr:`.real`, :attr:`.imag`, ``+``,
-   ``-``, ``*``, ``/``, :func:`abs`, :meth:`conjugate`, ``==``, and ``!=``. All
-   except ``-`` and ``!=`` are abstract.
+   ``-``, ``*``, ``/``, ``**``, :func:`abs`, :meth:`conjugate`, ``==``, and
+   ``!=``. All except ``-`` and ``!=`` are abstract.
 
    .. attribute:: real
 
@@ -76,8 +76,9 @@ The numeric tower
 
    Subtypes :class:`Rational` and adds a conversion to :class:`int`.  Provides
    defaults for :func:`float`, :attr:`~Rational.numerator`, and
-   :attr:`~Rational.denominator`.  Adds abstract methods for ``**`` and
-   bit-string operations: ``<<``, ``>>``, ``&``, ``^``, ``|``, ``~``.
+   :attr:`~Rational.denominator`.  Adds abstract methods for :func:`pow` with
+   modulus and bit-string operations: ``<<``, ``>>``, ``&``, ``^``, ``|``,
+   ``~``.
 
 
 Notes for type implementors

diff --git a/Doc/library/zipfile.rst b/Doc/library/zipfile.rst
@@ -521,6 +521,27 @@ Path objects are traversable using the ``/`` operator or ``joinpath``.
    Return ``True`` if the current context references a file or
    directory in the zip file.
 
+.. data:: Path.suffix
+
+   The file extension of the final component.
+
+   .. versionadded:: 3.11
+      Added :data:`Path.suffix` property.
+
+.. data:: Path.stem
+
+   The final path component, without its suffix.
+
+   .. versionadded:: 3.11
+      Added :data:`Path.stem` property.
+
+.. data:: Path.suffixes
+
+   A list of the path’s file extensions.
+
+   .. versionadded:: 3.11
+      Added :data:`Path.suffixes` property.
+
 .. method:: Path.read_text(*, **)
 
    Read the current file as unicode text. Positional and

diff --git a/Doc/reference/compound_stmts.rst b/Doc/reference/compound_stmts.rst
@@ -254,7 +254,7 @@ is found that matches the exception.  An expression-less except clause, if
 present, must be last; it matches any exception.  For an except clause with an
 expression, that expression is evaluated, and the clause matches the exception
 if the resulting object is "compatible" with the exception.  An object is
-compatible with an exception if it is the class or a base class of the exception
+compatible with an exception if the object is the class or a base class of the exception
 object, or a tuple containing an item that is the class or a base class of
 the exception object.
 
@@ -822,7 +822,7 @@ and binds no name.  Syntax:
 
 ``_`` is a :ref:`soft keyword <soft-keywords>` within any pattern,
 but only within patterns.  It is an identifier, as usual, even within
-``match`` headers, ``guards``, and ``case`` blocks.
+``match`` subject expressions, ``guard``\ s, and ``case`` blocks.
 
 In simple terms, ``_`` will always succeed.
 
@@ -900,8 +900,8 @@ sequence pattern.
 The following is the logical flow for matching a sequence pattern against a
 subject value:
 
-#. If the subject value is not an instance of a
-   :class:`collections.abc.Sequence` the sequence pattern fails.
+#. If the subject value is not a sequence [#]_, the sequence pattern
+   fails.
 
 #. If the subject value is an instance of ``str``, ``bytes`` or ``bytearray``
    the sequence pattern fails.
@@ -943,7 +943,7 @@ subject value:
 In simple terms ``[P1, P2, P3,`` ... ``, P<N>]`` matches only if all the following
 happens:
 
-* ``isinstance(<subject>, collections.abc.Sequence)``
+* check ``<subject>`` is a sequence
 * ``len(subject) == <N>``
 * ``P1`` matches ``<subject>[0]`` (note that this match can also bind names)
 * ``P2`` matches ``<subject>[1]`` (note that this match can also bind names)
@@ -975,8 +975,7 @@ runtime error and will raise :exc:`ValueError`.)
 The following is the logical flow for matching a mapping pattern against a
 subject value:
 
-#. If the subject value is not an instance of :class:`collections.abc.Mapping`,
-   the mapping pattern fails.
+#. If the subject value is not a mapping [#]_,the mapping pattern fails.
 
 #. If every key given in the mapping pattern is present in the subject mapping,
    and the pattern for each key matches the corresponding item of the subject
@@ -993,7 +992,7 @@ subject value:
 In simple terms ``{KEY1: P1, KEY2: P2, ... }`` matches only if all the following
 happens:
 
-* ``isinstance(<subject>, collections.abc.Mapping)``
+* check ``<subject>`` is a mapping
 * ``KEY1 in <subject>``
 * ``P1`` matches ``<subject>[KEY1]``
 * ... and so on for the corresponding KEY/pattern pair.
@@ -1526,6 +1525,35 @@ body of a coroutine function.
    there is a :keyword:`finally` clause which happens to raise another
    exception. That new exception causes the old one to be lost.
 
+.. [#] In pattern matching, a sequence is defined as one of the following:
+
+      * a class that inherits from :class:`collections.abc.Sequence`
+      * a Python class that has been registered as :class:`collections.abc.Sequence`
+      * a builtin class that has its (CPython) :data:`Py_TPFLAGS_SEQUENCE` bit set
+      * a class that inherits from any of the above
+
+   The following standard library classes are sequences:
+
+      * :class:`array.array`
+      * :class:`collections.deque`
+      * :class:`list`
+      * :class:`memoryview`
+      * :class:`range`
+      * :class:`tuple`
+
+   .. note:: Subject values of type ``str``, ``bytes``, and ``bytearray``
+      do not match sequence patterns.
+
+.. [#] In pattern matching, a mapping is defined as one of the following:
+
+      * a class that inherits from :class:`collections.abc.Mapping`
+      * a Python class that has been registered as :class:`collections.abc.Mapping`
+      * a builtin class that has its (CPython) :data:`Py_TPFLAGS_MAPPING` bit set
+      * a class that inherits from any of the above
+
+   The standard library classes :class:`dict` and :class:`types.MappingProxyType`
+   are mappings.
+
 .. [#] A string literal appearing as the first statement in the function body is
    transformed into the function's ``__doc__`` attribute and therefore the
    function's :term:`docstring`.

diff --git a/Doc/reference/simple_stmts.rst b/Doc/reference/simple_stmts.rst
@@ -734,7 +734,7 @@ The :keyword:`!import` statement
               : ("," `identifier` ["as" `identifier`])*
               : | "from" `relative_module` "import" "(" `identifier` ["as" `identifier`]
               : ("," `identifier` ["as" `identifier`])* [","] ")"
-              : | "from" `module` "import" "*"
+              : | "from" `relative_module` "import" "*"
    module: (`identifier` ".")* `identifier`
    relative_module: "."* `module` | "."+
 

diff --git a/Doc/tutorial/introduction.rst b/Doc/tutorial/introduction.rst
@@ -73,7 +73,7 @@ operator; to calculate the remainder you can use ``%``::
    5
    >>> 17 % 3  # the % operator returns the remainder of the division
    2
-   >>> 5 * 3 + 2  # result * divisor + remainder
+   >>> 5 * 3 + 2  # floored quotient * divisor + remainder
    17
 
 With Python, it is possible to use the ``**`` operator to calculate powers [#]_::

diff --git a/Doc/whatsnew/3.10.rst b/Doc/whatsnew/3.10.rst
@@ -589,7 +589,7 @@ Several other key features:
 
 - Like unpacking assignments, tuple and list patterns have exactly the
   same meaning and actually match arbitrary sequences. Technically,
-  the subject must be an instance of ``collections.abc.Sequence``.
+  the subject must be a sequence.
   Therefore, an important exception is that patterns don't match iterators.
   Also, to prevent a common mistake, sequence patterns don't match strings.
 
@@ -1089,6 +1089,14 @@ Add :data:`~os.O_EVTONLY`, :data:`~os.O_FSYNC`, :data:`~os.O_SYMLINK`
 and :data:`~os.O_NOFOLLOW_ANY` for macOS.
 (Contributed by Dong-hee Na in :issue:`43106`.)
 
+os.path
+-------
+
+:func:`os.path.realpath` now accepts a *strict* keyword-only argument. When set
+to ``True``, :exc:`OSError` is raised if a path doesn't exist or a symlink loop
+is encountered.
+(Contributed by Barney Gale in :issue:`43757`.)
+
 pathlib
 -------
 
@@ -1104,6 +1112,11 @@ supersedes :meth:`~pathlib.Path.link_to`. The new method has the same argument
 order as :meth:`~pathlib.Path.symlink_to`.
 (Contributed by Barney Gale in :issue:`39950`.)
 
+:meth:`pathlib.Path.stat` and :meth:`~pathlib.Path.chmod` now accept a
+*follow_symlinks* keyword-only argument for consistency with corresponding
+functions in the :mod:`os` module.
+(Contributed by Barney Gale in :issue:`39906`.)
+
 platform
 --------
 
@@ -1833,6 +1846,10 @@ New Features
   creating type instances.
   (Contributed by Victor Stinner in :issue:`43916`.)
 
+* Add a new :c:data:`Py_TPFLAGS_IMMUTABLETYPE` type flag for creating immutable
+  type objects: type attributes cannot be set nor deleted.
+  (Contributed by Victor Stinner and Erlend E. Aasland in :issue:`43908`.)
+
 Porting to Python 3.10
 ----------------------
 
@@ -1890,6 +1907,12 @@ Porting to Python 3.10
   been included directly, consider including ``Python.h`` instead.
   (Contributed by Nicholas Sim in :issue:`35134`)
 
+* Use the :c:data:`Py_TPFLAGS_IMMUTABLETYPE` type flag to create immutable type
+  objects. Do not rely on :c:data:`Py_TPFLAGS_HEAPTYPE` to decide if a type
+  object is mutable or not; check if :c:data:`Py_TPFLAGS_IMMUTABLETYPE` is set
+  instead.
+  (Contributed by Victor Stinner and Erlend E. Aasland in :issue:`43908`.)
+
 Deprecated
 ----------
 

diff --git a/Include/cpython/pyerrors.h b/Include/cpython/pyerrors.h
@@ -91,14 +91,6 @@ PyAPI_FUNC(void) _PyErr_GetExcInfo(PyThreadState *, PyObject **, PyObject **, Py
 
 PyAPI_FUNC(void) _PyErr_ChainExceptions(PyObject *, PyObject *, PyObject *);
 
-/* Convenience functions */
-
-#ifdef MS_WINDOWS
-Py_DEPRECATED(3.3)
-PyAPI_FUNC(PyObject *) PyErr_SetFromErrnoWithUnicodeFilename(
-    PyObject *, const Py_UNICODE *);
-#endif /* MS_WINDOWS */
-
 /* Like PyErr_Format(), but saves current exception as __context__ and
    __cause__.
  */
@@ -108,16 +100,6 @@ PyAPI_FUNC(PyObject *) _PyErr_FormatFromCause(
     ...
     );
 
-#ifdef MS_WINDOWS
-/* XXX redeclare to use WSTRING */
-Py_DEPRECATED(3.3)
-PyAPI_FUNC(PyObject *) PyErr_SetFromWindowsErrWithUnicodeFilename(
-    int, const Py_UNICODE *);
-Py_DEPRECATED(3.3)
-PyAPI_FUNC(PyObject *) PyErr_SetExcFromWindowsErrWithUnicodeFilename(
-    PyObject *,int, const Py_UNICODE *);
-#endif
-
 /* In exceptions.c */
 
 /* Helper that attempts to replace the current exception with one of the