mirror of https://github.com/python/cpython
780 lines
30 KiB
ReStructuredText
780 lines
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ReStructuredText
****************************
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What's New In Python 3.10
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****************************
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:Release: |release|
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:Date: |today|
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.. Rules for maintenance:
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* Anyone can add text to this document. Do not spend very much time
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on the wording of your changes, because your text will probably
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get rewritten to some degree.
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* The maintainer will go through Misc/NEWS periodically and add
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changes; it's therefore more important to add your changes to
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Misc/NEWS than to this file.
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* This is not a complete list of every single change; completeness
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is the purpose of Misc/NEWS. Some changes I consider too small
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or esoteric to include. If such a change is added to the text,
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I'll just remove it. (This is another reason you shouldn't spend
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too much time on writing your addition.)
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* If you want to draw your new text to the attention of the
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maintainer, add 'XXX' to the beginning of the paragraph or
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section.
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* It's OK to just add a fragmentary note about a change. For
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example: "XXX Describe the transmogrify() function added to the
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socket module." The maintainer will research the change and
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write the necessary text.
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* You can comment out your additions if you like, but it's not
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necessary (especially when a final release is some months away).
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* Credit the author of a patch or bugfix. Just the name is
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sufficient; the e-mail address isn't necessary.
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* It's helpful to add the bug/patch number as a comment:
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XXX Describe the transmogrify() function added to the socket
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module.
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(Contributed by P.Y. Developer in :issue:`12345`.)
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This saves the maintainer the effort of going through the Mercurial log
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when researching a change.
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This article explains the new features in Python 3.10, compared to 3.9.
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For full details, see the :ref:`changelog <changelog>`.
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.. note::
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Prerelease users should be aware that this document is currently in draft
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form. It will be updated substantially as Python 3.10 moves towards release,
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so it's worth checking back even after reading earlier versions.
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Summary -- Release highlights
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=============================
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.. This section singles out the most important changes in Python 3.10.
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Brevity is key.
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.. PEP-sized items next.
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New Features
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============
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.. _whatsnew310-pep563:
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PEP 563: Postponed Evaluation of Annotations Becomes Default
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------------------------------------------------------------
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In Python 3.7, postponed evaluation of annotations was added,
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to be enabled with a ``from __future__ import annotations``
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directive. In 3.10 this became the default behavior, even
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without that future directive. With this being default, all
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annotations stored in :attr:`__annotations__` will be strings.
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If needed, annotations can be resolved at runtime using
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:func:`typing.get_type_hints`. See :pep:`563` for a full
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description. Also, the :func:`inspect.signature` will try to
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resolve types from now on, and when it fails it will fall back to
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showing the string annotations. (Contributed by Batuhan Taskaya
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in :issue:`38605`.)
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* The :class:`int` type has a new method :meth:`int.bit_count`, returning the
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number of ones in the binary expansion of a given integer, also known
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as the population count. (Contributed by Niklas Fiekas in :issue:`29882`.)
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* The views returned by :meth:`dict.keys`, :meth:`dict.values` and
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:meth:`dict.items` now all have a ``mapping`` attribute that gives a
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:class:`types.MappingProxyType` object wrapping the original
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dictionary. (Contributed by Dennis Sweeney in :issue:`40890`.)
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* :pep:`618`: The :func:`zip` function now has an optional ``strict`` flag, used
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to require that all the iterables have an equal length.
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PEP 613: TypeAlias Annotation
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-----------------------------
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:pep:`484` introduced the concept of type aliases, only requiring them to be
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top-level unannotated assignments. This simplicity sometimes made it difficult
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for type checkers to distinguish between type aliases and ordinary assignments,
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especially when forward references or invalid types were involved. Compare::
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StrCache = 'Cache[str]' # a type alias
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LOG_PREFIX = 'LOG[DEBUG]' # a module constant
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Now the :mod:`typing` module has a special annotation :data:`TypeAlias` to
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declare type aliases more explicitly::
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StrCache: TypeAlias = 'Cache[str]' # a type alias
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LOG_PREFIX = 'LOG[DEBUG]' # a module constant
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See :pep:`613` for more details.
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(Contributed by Mikhail Golubev in :issue:`41923`.)
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PEP 604: New Type Union Operator
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--------------------------------
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A new type union operator was introduced which enables the syntax ``X | Y``.
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This provides a cleaner way of expressing 'either type X or type Y' instead of
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using :data:`typing.Union`, especially in type hints (annotations).
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In previous versions of Python, to apply a type hint for functions accepting
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arguments of multiple types, :data:`typing.Union` was used::
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def square(number: Union[int, float]) -> Union[int, float]:
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return number ** 2
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Type hints can now be written in a more succinct manner::
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def square(number: int | float) -> int | float:
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return number ** 2
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See :pep:`604` for more details.
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(Contributed by Maggie Moss and Philippe Prados in :issue:`41428`.)
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PEP 612: Parameter Specification Variables
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------------------------------------------
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Two new options to improve the information provided to static type checkers for
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:pep:`484`\ 's ``Callable`` have been added to the :mod:`typing` module.
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The first is the parameter specification variable. They are used to forward the
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parameter types of one callable to another callable -- a pattern commonly
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found in higher order functions and decorators. Examples of usage can be found
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in :class:`typing.ParamSpec`. Previously, there was no easy way to type annotate
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dependency of parameter types in such a precise manner.
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The second option is the new ``Concatenate`` operator. It's used in conjunction
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with parameter specification variables to type annotate a higher order callable
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which adds or removes parameters of another callable. Examples of usage can
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be found in :class:`typing.Concatenate`.
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See :class:`typing.Callable`, :class:`typing.ParamSpec`,
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:class:`typing.Concatenate` and :pep:`612` for more details.
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(Contributed by Ken Jin in :issue:`41559`.)
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Other Language Changes
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======================
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* Builtin and extension functions that take integer arguments no longer accept
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:class:`~decimal.Decimal`\ s, :class:`~fractions.Fraction`\ s and other
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objects that can be converted to integers only with a loss (e.g. that have
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the :meth:`~object.__int__` method but do not have the
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:meth:`~object.__index__` method).
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(Contributed by Serhiy Storchaka in :issue:`37999`.)
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* Assignment expressions can now be used unparenthesized within set literals
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and set comprehensions, as well as in sequence indexes (but not slices).
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New Modules
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===========
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* None yet.
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Improved Modules
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================
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argparse
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--------
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Misleading phrase "optional arguments" was replaced with "options" in argparse help. Some tests might require adaptation if they rely on exact output match.
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(Contributed by Raymond Hettinger in :issue:`9694`.)
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base64
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------
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Add :func:`base64.b32hexencode` and :func:`base64.b32hexdecode` to support the
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Base32 Encoding with Extended Hex Alphabet.
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codecs
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------
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Add a :func:`codecs.unregister` function to unregister a codec search function.
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(Contributed by Hai Shi in :issue:`41842`.)
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collections.abc
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---------------
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The ``__args__`` of the :ref:`parameterized generic <types-genericalias>` for
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:class:`collections.abc.Callable` are now consistent with :data:`typing.Callable`.
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:class:`collections.abc.Callable` generic now flattens type parameters, similar
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to what :data:`typing.Callable` currently does. This means that
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``collections.abc.Callable[[int, str], str]`` will have ``__args__`` of
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``(int, str, str)``; previously this was ``([int, str], str)``. To allow this
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change, :class:`types.GenericAlias` can now be subclassed, and a subclass will
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be returned when subscripting the :class:`collections.abc.Callable` type. Note
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that a :exc:`TypeError` may be raised for invalid forms of parameterizing
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:class:`collections.abc.Callable` which may have passed silently in Python 3.9.
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(Contributed by Ken Jin in :issue:`42195`.)
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contextlib
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----------
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Add a :func:`contextlib.aclosing` context manager to safely close async generators
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and objects representing asynchronously released resources.
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(Contributed by Joongi Kim and John Belmonte in :issue:`41229`.)
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Add asynchronous context manager support to :func:`contextlib.nullcontext`.
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(Contributed by Tom Gringauz in :issue:`41543`.)
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curses
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------
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The extended color functions added in ncurses 6.1 will be used transparently
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by :func:`curses.color_content`, :func:`curses.init_color`,
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:func:`curses.init_pair`, and :func:`curses.pair_content`. A new function,
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:func:`curses.has_extended_color_support`, indicates whether extended color
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support is provided by the underlying ncurses library.
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(Contributed by Jeffrey Kintscher and Hans Petter Jansson in :issue:`36982`.)
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The ``BUTTON5_*`` constants are now exposed in the :mod:`curses` module if
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they are provided by the underlying curses library.
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(Contributed by Zackery Spytz in :issue:`39273`.)
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distutils
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---------
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The ``bdist_wininst`` command deprecated in Python 3.8 has been removed.
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The ``bidst_wheel`` command is now recommended to distribute binary packages
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on Windows.
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(Contributed by Victor Stinner in :issue:`42802`.)
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doctest
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-------
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When a module does not define ``__loader__``, fall back to ``__spec__.loader``.
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(Contributed by Brett Cannon in :issue:`42133`.)
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encodings
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---------
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:func:`encodings.normalize_encoding` now ignores non-ASCII characters.
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(Contributed by Hai Shi in :issue:`39337`.)
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glob
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----
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Added the *root_dir* and *dir_fd* parameters in :func:`~glob.glob` and
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:func:`~glob.iglob` which allow to specify the root directory for searching.
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(Contributed by Serhiy Storchaka in :issue:`38144`.)
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inspect
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-------
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When a module does not define ``__loader__``, fall back to ``__spec__.loader``.
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(Contributed by Brett Cannon in :issue:`42133`.)
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Added *globalns* and *localns* parameters in :func:`~inspect.signature` and
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:meth:`inspect.Signature.from_callable` to retrieve the annotations in given
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local and global namespaces.
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(Contributed by Batuhan Taskaya in :issue:`41960`.)
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linecache
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---------
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When a module does not define ``__loader__``, fall back to ``__spec__.loader``.
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(Contributed by Brett Cannon in :issue:`42133`.)
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os
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--
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Added :func:`os.cpu_count()` support for VxWorks RTOS.
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(Contributed by Peixing Xin in :issue:`41440`.)
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Added a new function :func:`os.eventfd` and related helpers to wrap the
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``eventfd2`` syscall on Linux.
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(Contributed by Christian Heimes in :issue:`41001`.)
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Added :func:`os.splice()` that allows to move data between two file
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descriptors without copying between kernel address space and user
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address space, where one of the file descriptors must refer to a
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pipe. (Contributed by Pablo Galindo in :issue:`41625`.)
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pathlib
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-------
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Added slice support to :attr:`PurePath.parents <pathlib.PurePath.parents>`.
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(Contributed by Joshua Cannon in :issue:`35498`)
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Added negative indexing support to :attr:`PurePath.parents
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<pathlib.PurePath.parents>`.
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(Contributed by Yaroslav Pankovych in :issue:`21041`)
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platform
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--------
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Added :func:`platform.freedesktop_os_release()` to retrieve operation system
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identification from `freedesktop.org os-release
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<https://www.freedesktop.org/software/systemd/man/os-release.html>`_ standard file.
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(Contributed by Christian Heimes in :issue:`28468`)
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py_compile
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----------
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Added ``--quiet`` option to command-line interface of :mod:`py_compile`.
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(Contributed by Gregory Schevchenko in :issue:`38731`.)
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shelve
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------
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The :mod:`shelve` module now uses :data:`pickle.DEFAULT_PROTOCOL` by default
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instead of :mod:`pickle` protocol ``3`` when creating shelves.
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(Contributed by Zackery Spytz in :issue:`34204`.)
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site
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----
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When a module does not define ``__loader__``, fall back to ``__spec__.loader``.
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(Contributed by Brett Cannon in :issue:`42133`.)
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socket
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------
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The exception :exc:`socket.timeout` is now an alias of :exc:`TimeoutError`.
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(Contributed by Christian Heimes in :issue:`42413`.)
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sys
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---
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Add :data:`sys.orig_argv` attribute: the list of the original command line
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arguments passed to the Python executable.
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(Contributed by Victor Stinner in :issue:`23427`.)
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threading
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---------
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Added :func:`threading.gettrace` and :func:`threading.getprofile` to
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retrieve the functions set by :func:`threading.settrace` and
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:func:`threading.setprofile` respectively.
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(Contributed by Mario Corchero in :issue:`42251`.)
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Add :data:`threading.__excepthook__` to allow retrieving the original value
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of :func:`threading.excepthook` in case it is set to a broken or a different
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value.
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(Contributed by Mario Corchero in :issue:`42308`.)
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traceback
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---------
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The :func:`~traceback.format_exception`,
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:func:`~traceback.format_exception_only`, and
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:func:`~traceback.print_exception` functions can now take an exception object
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as a positional-only argument.
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(Contributed by Zackery Spytz and Matthias Bussonnier in :issue:`26389`.)
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types
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-----
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Reintroduced the :data:`types.EllipsisType`, :data:`types.NoneType`
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and :data:`types.NotImplementedType` classes, providing a new set
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of types readily interpretable by type checkers.
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(Contributed by Bas van Beek in :issue:`41810`.)
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typing
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------
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The behavior of :class:`typing.Literal` was changed to conform with :pep:`586`
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and to match the behavior of static type checkers specified in the PEP.
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1. ``Literal`` now de-duplicates parameters.
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2. Equality comparisons between ``Literal`` objects are now order independent.
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3. ``Literal`` comparisons now respects types. For example,
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``Literal[0] == Literal[False]`` previously evaluated to ``True``. It is
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now ``False``. To support this change, the internally used type cache now
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supports differentiating types.
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4. ``Literal`` objects will now raise a :exc:`TypeError` exception during
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equality comparisons if one of their parameters are not :term:`immutable`.
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Note that declaring ``Literal`` with mutable parameters will not throw
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an error::
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>>> from typing import Literal
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>>> Literal[{0}]
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>>> Literal[{0}] == Literal[{False}]
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Traceback (most recent call last):
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File "<stdin>", line 1, in <module>
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TypeError: unhashable type: 'set'
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(Contributed by Yurii Karabas in :issue:`42345`.)
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unittest
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--------
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Add new method :meth:`~unittest.TestCase.assertNoLogs` to complement the
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existing :meth:`~unittest.TestCase.assertLogs`. (Contributed by Kit Yan Choi
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in :issue:`39385`.)
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xml
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---
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Add a :class:`~xml.sax.handler.LexicalHandler` class to the
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:mod:`xml.sax.handler` module.
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(Contributed by Jonathan Gossage and Zackery Spytz in :issue:`35018`.)
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zipimport
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---------
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Add methods related to :pep:`451`: :meth:`~zipimport.zipimporter.find_spec`,
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:meth:`zipimport.zipimporter.create_module`, and
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:meth:`zipimport.zipimporter.exec_module`.
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(Contributed by Brett Cannon in :issue:`42131`.
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Optimizations
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=============
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* Constructors :func:`str`, :func:`bytes` and :func:`bytearray` are now faster
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(around 30--40% for small objects).
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(Contributed by Serhiy Storchaka in :issue:`41334`.)
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* The :mod:`runpy` module now imports fewer modules.
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The ``python3 -m module-name`` command startup time is 1.3x faster in
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average.
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(Contributed by Victor Stinner in :issue:`41006`.)
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* The ``LOAD_ATTR`` instruction now uses new "per opcode cache" mechanism. It
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is about 36% faster now. This makes optimized ``LOAD_ATTR`` instructions the
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current most performance attribute access method (faster than slots).
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(Contributed by Pablo Galindo and Yury Selivanov in :issue:`42093`, based on
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ideas implemented originally in PyPy and MicroPython.)
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* When building Python with ``--enable-optimizations`` now
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``-fno-semantic-interposition`` is added to both the compile and link line.
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This speeds builds of the Python interpreter created with ``--enable-shared``
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with ``gcc`` by up to 30%. See `this article
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<https://developers.redhat.com/blog/2020/06/25/red-hat-enterprise-linux-8-2-brings-faster-python-3-8-run-speeds/>`_
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for more details. (Contributed by Victor Stinner and Pablo Galindo in
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:issue:`38980`.)
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* Function parameters and their annotations are no longer computed at runtime,
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but rather at compilation time. They are stored as a tuple of strings at the
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bytecode level. It is now around 100% faster to create a function with parameter
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annotations. (Contributed by Yurii Karabas and Inada Naoki in :issue:`42202`)
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Deprecated
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==========
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* Starting in this release, there will be a concerted effort to begin
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cleaning up old import semantics that were kept for Python 2.7
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compatibility. Specifically,
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:meth:`~importlib.abc.PathEntryFinder.find_loader`/:meth:`~importlib.abc.Finder.find_module`
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(superseded by :meth:`~importlib.abc.Finder.find_spec`),
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:meth:`~importlib.abc.Loader.load_module`
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(superseded by :meth:`~importlib.abc.Loader.exec_module`),
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:meth:`~importlib.abc.Loader.module_repr` (which the import system
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takes care of for you), the ``__package__`` attribute
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(superseded by ``__spec__.parent``), the ``__loader__`` attribute
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(superseded by ``__spec__.loader``), and the ``__cached__`` attribute
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(superseded by ``__spec__.cached``) will slowly be removed (as well
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as other classes and methods in :mod:`importlib`).
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:exc:`ImportWarning` and/or :exc:`DeprecationWarning` will be raised
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as appropriate to help identify code which needs updating during
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this transition.
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* The various ``load_module()`` methods of :mod:`importlib` have been
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documented as deprecated since Python 3.6, but will now also trigger
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a :exc:`DeprecationWarning`. Use
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:meth:`~importlib.abc.Loader.exec_module` instead.
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(Contributed by Brett Cannon in :issue:`26131`.)
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* :meth:`zimport.zipimporter.load_module` has been deprecated in
|
|
preference for :meth:`~zipimport.zipimporter.exec_module`.
|
|
(Contributed by Brett Cannon in :issue:`26131`.)
|
|
|
|
* The use of :meth:`~importlib.abc.Loader.load_module` by the import
|
|
system now triggers an :exc:`ImportWarning` as
|
|
:meth:`~importlib.abc.Loader.exec_module` is preferred.
|
|
(Contributed by Brett Cannon in :issue:`26131`.)
|
|
|
|
* ``sqlite3.OptimizedUnicode`` has been undocumented and obsolete since Python
|
|
3.3, when it was made an alias to :class:`str`. It is now deprecated,
|
|
scheduled for removal in Python 3.12.
|
|
(Contributed by Erlend E. Aasland in :issue:`42264`.)
|
|
|
|
* The undocumented built-in function ``sqlite3.enable_shared_cache`` is now
|
|
deprecated, scheduled for removal in Python 3.12. Its use is strongly
|
|
discouraged by the SQLite3 documentation. See `the SQLite3 docs
|
|
<https://sqlite.org/c3ref/enable_shared_cache.html/>`_ for more details.
|
|
If shared cache must be used, open the database in URI mode using the
|
|
``cache=shared`` query parameter.
|
|
(Contributed by Erlend E. Aasland in :issue:`24464`.)
|
|
|
|
|
|
Removed
|
|
=======
|
|
|
|
* Removed special methods ``__int__``, ``__float__``, ``__floordiv__``,
|
|
``__mod__``, ``__divmod__``, ``__rfloordiv__``, ``__rmod__`` and
|
|
``__rdivmod__`` of the :class:`complex` class. They always raised
|
|
a :exc:`TypeError`.
|
|
(Contributed by Serhiy Storchaka in :issue:`41974`.)
|
|
|
|
* The ``ParserBase.error()`` method from the private and undocumented ``_markupbase``
|
|
module has been removed. :class:`html.parser.HTMLParser` is the only subclass of
|
|
``ParserBase`` and its ``error()`` implementation has already been removed in
|
|
Python 3.5.
|
|
(Contributed by Berker Peksag in :issue:`31844`.)
|
|
|
|
* Removed the ``unicodedata.ucnhash_CAPI`` attribute which was an internal
|
|
PyCapsule object. The related private ``_PyUnicode_Name_CAPI`` structure was
|
|
moved to the internal C API.
|
|
(Contributed by Victor Stinner in :issue:`42157`.)
|
|
|
|
* Removed the ``parser`` module, which was deprecated in 3.9 due to the
|
|
switch to the new PEG parser, as well as all the C source and header files
|
|
that were only being used by the old parser, including ``node.h``, ``parser.h``,
|
|
``graminit.h`` and ``grammar.h``.
|
|
|
|
* Removed the Public C API functions :c:func:`PyParser_SimpleParseStringFlags`,
|
|
:c:func:`PyParser_SimpleParseStringFlagsFilename`,
|
|
:c:func:`PyParser_SimpleParseFileFlags` and :c:func:`PyNode_Compile`
|
|
that were deprecated in 3.9 due to the switch to the new PEG parser.
|
|
|
|
* Removed the ``formatter`` module, which was deprecated in Python 3.4.
|
|
It is somewhat obsolete, little used, and not tested. It was originally
|
|
scheduled to be removed in Python 3.6, but such removals were delayed until
|
|
after Python 2.7 EOL. Existing users should copy whatever classes they use
|
|
into their code.
|
|
(Contributed by Dong-hee Na and Terry J. Reedy in :issue:`42299`.)
|
|
|
|
* Removed the :c:func:`PyModule_GetWarningsModule` function that was useless
|
|
now due to the _warnings module was converted to a builtin module in 2.6.
|
|
(Contributed by Hai Shi in :issue:`42599`.)
|
|
|
|
* Remove deprecated aliases to :ref:`collections-abstract-base-classes` from
|
|
the :mod:`collections` module.
|
|
(Contributed by Victor Stinner in :issue:`37324`.)
|
|
|
|
|
|
Porting to Python 3.10
|
|
======================
|
|
|
|
This section lists previously described changes and other bugfixes
|
|
that may require changes to your code.
|
|
|
|
|
|
Changes in the Python API
|
|
-------------------------
|
|
|
|
* The *etype* parameters of the :func:`~traceback.format_exception`,
|
|
:func:`~traceback.format_exception_only`, and
|
|
:func:`~traceback.print_exception` functions in the :mod:`traceback` module
|
|
have been renamed to *exc*.
|
|
(Contributed by Zackery Spytz and Matthias Bussonnier in :issue:`26389`.)
|
|
|
|
* :mod:`atexit`: At Python exit, if a callback registered with
|
|
:func:`atexit.register` fails, its exception is now logged. Previously, only
|
|
some exceptions were logged, and the last exception was always silently
|
|
ignored.
|
|
(Contributed by Victor Stinner in :issue:`42639`.)
|
|
|
|
* :class:`collections.abc.Callable` generic now flattens type parameters, similar
|
|
to what :data:`typing.Callable` currently does. This means that
|
|
``collections.abc.Callable[[int, str], str]`` will have ``__args__`` of
|
|
``(int, str, str)``; previously this was ``([int, str], str)``. Code which
|
|
accesses the arguments via :func:`typing.get_args` or ``__args__`` need to account
|
|
for this change. Furthermore, :exc:`TypeError` may be raised for invalid forms
|
|
of parameterizing :class:`collections.abc.Callable` which may have passed
|
|
silently in Python 3.9.
|
|
(Contributed by Ken Jin in :issue:`42195`.)
|
|
|
|
* :meth:`socket.htons` and :meth:`socket.ntohs` now raise :exc:`OverflowError`
|
|
instead of :exc:`DeprecationWarning` if the given parameter will not fit in
|
|
a 16-bit unsigned integer.
|
|
(Contributed by Erlend E. Aasland in :issue:`42393`.)
|
|
|
|
|
|
CPython bytecode changes
|
|
========================
|
|
|
|
* The ``MAKE_FUNCTION`` instruction accepts tuple of strings as annotations
|
|
instead of dictionary.
|
|
(Contributed by Yurii Karabas and Inada Naoki in :issue:`42202`)
|
|
|
|
Build Changes
|
|
=============
|
|
|
|
* The C99 functions :c:func:`snprintf` and :c:func:`vsnprintf` are now required
|
|
to build Python.
|
|
(Contributed by Victor Stinner in :issue:`36020`.)
|
|
|
|
* :mod:`sqlite3` requires SQLite 3.7.15 or higher. (Contributed by Sergey Fedoseev
|
|
and Erlend E. Aasland :issue:`40744` and :issue:`40810`.)
|
|
|
|
* The :mod:`atexit` module must now always be built as a built-in module.
|
|
(Contributed by Victor Stinner in :issue:`42639`.)
|
|
|
|
* Added ``--disable-test-modules`` option to the ``configure`` script:
|
|
don't build nor install test modules.
|
|
(Contributed by Xavier de Gaye, Thomas Petazzoni and Peixing Xin in :issue:`27640`.)
|
|
|
|
|
|
C API Changes
|
|
=============
|
|
|
|
New Features
|
|
------------
|
|
|
|
* The result of :c:func:`PyNumber_Index` now always has exact type :class:`int`.
|
|
Previously, the result could have been an instance of a subclass of ``int``.
|
|
(Contributed by Serhiy Storchaka in :issue:`40792`.)
|
|
|
|
* Add a new :c:member:`~PyConfig.orig_argv` member to the :c:type:`PyConfig`
|
|
structure: the list of the original command line arguments passed to the
|
|
Python executable.
|
|
(Contributed by Victor Stinner in :issue:`23427`.)
|
|
|
|
* The :c:func:`PyDateTime_DATE_GET_TZINFO` and
|
|
:c:func:`PyDateTime_TIME_GET_TZINFO` macros have been added for accessing
|
|
the ``tzinfo`` attributes of :class:`datetime.datetime` and
|
|
:class:`datetime.time` objects.
|
|
(Contributed by Zackery Spytz in :issue:`30155`.)
|
|
|
|
* Add a :c:func:`PyCodec_Unregister` function to unregister a codec
|
|
search function.
|
|
(Contributed by Hai Shi in :issue:`41842`.)
|
|
|
|
* The :c:func:`PyIter_Send` function was added to allow
|
|
sending value into iterator without raising ``StopIteration`` exception.
|
|
(Contributed by Vladimir Matveev in :issue:`41756`.)
|
|
|
|
* Added :c:func:`PyUnicode_AsUTF8AndSize` to the limited C API.
|
|
(Contributed by Alex Gaynor in :issue:`41784`.)
|
|
|
|
* Added :c:func:`PyModule_AddObjectRef` function: similar to
|
|
:c:func:`PyModule_AddObject` but don't steal a reference to the value on
|
|
success.
|
|
(Contributed by Victor Stinner in :issue:`1635741`.)
|
|
|
|
* Added :c:func:`Py_NewRef` and :c:func:`Py_XNewRef` functions to increment the
|
|
reference count of an object and return the object.
|
|
(Contributed by Victor Stinner in :issue:`42262`.)
|
|
|
|
* The :c:func:`PyType_FromSpecWithBases` and :c:func:`PyType_FromModuleAndSpec`
|
|
functions now accept a single class as the *bases* argument.
|
|
(Contributed by Serhiy Storchaka in :issue:`42423`.)
|
|
|
|
* The :c:func:`PyType_FromModuleAndSpec` function now accepts NULL ``tp_doc``
|
|
slot.
|
|
(Contributed by Hai Shi in :issue:`41832`.)
|
|
|
|
* The :c:func:`PyType_GetSlot` function can accept static types.
|
|
(Contributed by Hai Shi and Petr Viktorin in :issue:`41073`.)
|
|
|
|
|
|
Porting to Python 3.10
|
|
----------------------
|
|
|
|
* The ``PY_SSIZE_T_CLEAN`` macro must now be defined to use
|
|
:c:func:`PyArg_ParseTuple` and :c:func:`Py_BuildValue` formats which use
|
|
``#``: ``es#``, ``et#``, ``s#``, ``u#``, ``y#``, ``z#``, ``U#`` and ``Z#``.
|
|
See :ref:`Parsing arguments and building values
|
|
<arg-parsing>` and the :pep:`353`.
|
|
(Contributed by Victor Stinner in :issue:`40943`.)
|
|
|
|
* Since :c:func:`Py_REFCNT()` is changed to the inline static function,
|
|
``Py_REFCNT(obj) = new_refcnt`` must be replaced with ``Py_SET_REFCNT(obj, new_refcnt)``:
|
|
see :c:func:`Py_SET_REFCNT()` (available since Python 3.9). For backward
|
|
compatibility, this macro can be used::
|
|
|
|
#if PY_VERSION_HEX < 0x030900A4
|
|
# define Py_SET_REFCNT(obj, refcnt) ((Py_REFCNT(obj) = (refcnt)), (void)0)
|
|
#endif
|
|
|
|
(Contributed by Victor Stinner in :issue:`39573`.)
|
|
|
|
* Calling :c:func:`PyDict_GetItem` without :term:`GIL` held had been allowed
|
|
for historical reason. It is no longer allowed.
|
|
(Contributed by Victor Stinner in :issue:`40839`.)
|
|
|
|
* ``PyUnicode_FromUnicode(NULL, size)`` and ``PyUnicode_FromStringAndSize(NULL, size)``
|
|
raise ``DeprecationWarning`` now. Use :c:func:`PyUnicode_New` to allocate
|
|
Unicode object without initial data.
|
|
(Contributed by Inada Naoki in :issue:`36346`.)
|
|
|
|
* The private ``_PyUnicode_Name_CAPI`` structure of the PyCapsule API
|
|
``unicodedata.ucnhash_CAPI`` has been moved to the internal C API.
|
|
(Contributed by Victor Stinner in :issue:`42157`.)
|
|
|
|
* :c:func:`Py_GetPath`, :c:func:`Py_GetPrefix`, :c:func:`Py_GetExecPrefix`,
|
|
:c:func:`Py_GetProgramFullPath`, :c:func:`Py_GetPythonHome` and
|
|
:c:func:`Py_GetProgramName` functions now return ``NULL`` if called before
|
|
:c:func:`Py_Initialize` (before Python is initialized). Use the new
|
|
:ref:`Python Initialization Configuration API <init-config>` to get the
|
|
:ref:`Python Path Configuration. <init-path-config>`.
|
|
(Contributed by Victor Stinner in :issue:`42260`.)
|
|
|
|
* :c:func:`PyList_SET_ITEM`, :c:func:`PyTuple_SET_ITEM` and
|
|
:c:func:`PyCell_SET` macros can no longer be used as l-value or r-value.
|
|
For example, ``x = PyList_SET_ITEM(a, b, c)`` and
|
|
``PyList_SET_ITEM(a, b, c) = x`` now fail with a compiler error. It prevents
|
|
bugs like ``if (PyList_SET_ITEM (a, b, c) < 0) ...`` test.
|
|
(Contributed by Zackery Spytz and Victor Stinner in :issue:`30459`.)
|
|
|
|
Deprecated
|
|
----------
|
|
|
|
* The ``PyUnicode_InternImmortal()`` function is now deprecated
|
|
and will be removed in Python 3.12: use :c:func:`PyUnicode_InternInPlace`
|
|
instead.
|
|
(Contributed by Victor Stinner in :issue:`41692`.)
|
|
|
|
Removed
|
|
-------
|
|
|
|
* ``PyObject_AsCharBuffer()``, ``PyObject_AsReadBuffer()``, ``PyObject_CheckReadBuffer()``,
|
|
and ``PyObject_AsWriteBuffer()`` are removed. Please migrate to new buffer protocol;
|
|
:c:func:`PyObject_GetBuffer` and :c:func:`PyBuffer_Release`.
|
|
(Contributed by Inada Naoki in :issue:`41103`.)
|
|
|
|
* Removed ``Py_UNICODE_str*`` functions manipulating ``Py_UNICODE*`` strings.
|
|
(Contributed by Inada Naoki in :issue:`41123`.)
|
|
|
|
* ``Py_UNICODE_strlen``: use :c:func:`PyUnicode_GetLength` or
|
|
:c:macro:`PyUnicode_GET_LENGTH`
|
|
* ``Py_UNICODE_strcat``: use :c:func:`PyUnicode_CopyCharacters` or
|
|
:c:func:`PyUnicode_FromFormat`
|
|
* ``Py_UNICODE_strcpy``, ``Py_UNICODE_strncpy``: use
|
|
:c:func:`PyUnicode_CopyCharacters` or :c:func:`PyUnicode_Substring`
|
|
* ``Py_UNICODE_strcmp``: use :c:func:`PyUnicode_Compare`
|
|
* ``Py_UNICODE_strncmp``: use :c:func:`PyUnicode_Tailmatch`
|
|
* ``Py_UNICODE_strchr``, ``Py_UNICODE_strrchr``: use
|
|
:c:func:`PyUnicode_FindChar`
|
|
|
|
* Removed ``PyUnicode_GetMax()``. Please migrate to new (:pep:`393`) APIs.
|
|
(Contributed by Inada Naoki in :issue:`41103`.)
|
|
|
|
* Removed ``PyLong_FromUnicode()``. Please migrate to :c:func:`PyLong_FromUnicodeObject`.
|
|
(Contributed by Inada Naoki in :issue:`41103`.)
|
|
|
|
* Removed ``PyUnicode_AsUnicodeCopy()``. Please use :c:func:`PyUnicode_AsUCS4Copy` or
|
|
:c:func:`PyUnicode_AsWideCharString`
|
|
(Contributed by Inada Naoki in :issue:`41103`.)
|
|
|
|
* Removed ``_Py_CheckRecursionLimit`` variable: it has been replaced by
|
|
``ceval.recursion_limit`` of the :c:type:`PyInterpreterState` structure.
|
|
(Contributed by Victor Stinner in :issue:`41834`.)
|
|
|
|
* Removed undocumented macros ``Py_ALLOW_RECURSION`` and
|
|
``Py_END_ALLOW_RECURSION`` and the ``recursion_critical`` field of the
|
|
:c:type:`PyInterpreterState` structure.
|
|
(Contributed by Serhiy Storchaka in :issue:`41936`.)
|
|
|
|
* Removed the undocumented ``PyOS_InitInterrupts()`` function. Initializing
|
|
Python already implicitly installs signal handlers: see
|
|
:c:member:`PyConfig.install_signal_handlers`.
|
|
(Contributed by Victor Stinner in :issue:`41713`.)
|