mirror of https://github.com/python/cpython
983 lines
33 KiB
ReStructuredText
983 lines
33 KiB
ReStructuredText
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****************************
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What's new in Python 3.14
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****************************
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:Editor: TBD
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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 issue 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 :gh:`12345`.)
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This saves the maintainer the effort of going through the VCS log
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when researching a change.
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This article explains the new features in Python 3.14, compared to 3.13.
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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 3.14 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 3.14.
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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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.. _whatsnew314-pep649:
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PEP 649: deferred evaluation of annotations
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-------------------------------------------
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The :term:`annotations <annotation>` on functions, classes, and modules are no
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longer evaluated eagerly. Instead, annotations are stored in special-purpose
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:term:`annotate functions <annotate function>` and evaluated only when
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necessary. This is specified in :pep:`649` and :pep:`749`.
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This change is designed to make annotations in Python more performant and more
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usable in most circumstances. The runtime cost for defining annotations is
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minimized, but it remains possible to introspect annotations at runtime.
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It is usually no longer necessary to enclose annotations in strings if they
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contain forward references.
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The new :mod:`annotationlib` module provides tools for inspecting deferred
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annotations. Annotations may be evaluated in the :attr:`~annotationlib.Format.VALUE`
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format (which evaluates annotations to runtime values, similar to the behavior in
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earlier Python versions), the :attr:`~annotationlib.Format.FORWARDREF` format
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(which replaces undefined names with special markers), and the
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:attr:`~annotationlib.Format.STRING` format (which returns annotations as strings).
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This example shows how these formats behave:
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.. doctest::
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>>> from annotationlib import get_annotations, Format
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>>> def func(arg: Undefined):
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... pass
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>>> get_annotations(func, format=Format.VALUE)
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Traceback (most recent call last):
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...
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NameError: name 'Undefined' is not defined
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>>> get_annotations(func, format=Format.FORWARDREF)
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{'arg': ForwardRef('Undefined')}
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>>> get_annotations(func, format=Format.STRING)
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{'arg': 'Undefined'}
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Implications for annotated code
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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If you define annotations in your code (for example, for use with a static type
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checker), then this change probably does not affect you: you can keep
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writing annotations the same way you did with previous versions of Python.
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You will likely be able to remove quoted strings in annotations, which are frequently
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used for forward references. Similarly, if you use ``from __future__ import annotations``
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to avoid having to write strings in annotations, you may well be able to
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remove that import. However, if you rely on third-party libraries that read annotations,
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those libraries may need changes to support unquoted annotations before they
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work as expected.
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Implications for readers of ``__annotations__``
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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If your code reads the ``__annotations__`` attribute on objects, you may want
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to make changes in order to support code that relies on deferred evaluation of
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annotations. For example, you may want to use :func:`annotationlib.get_annotations`
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with the :attr:`~annotationlib.Format.FORWARDREF` format, as the :mod:`dataclasses`
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module now does.
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Related changes
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^^^^^^^^^^^^^^^
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The changes in Python 3.14 are designed to rework how ``__annotations__``
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works at runtime while minimizing breakage to code that contains
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annotations in source code and to code that reads ``__annotations__``. However,
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if you rely on undocumented details of the annotation behavior or on private
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functions in the standard library, there are many ways in which your code may
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not work in Python 3.14. To safeguard your code against future changes,
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use only the documented functionality of the :mod:`annotationlib` module.
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``from __future__ import annotations``
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^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
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In Python 3.7, :pep:`563` introduced the ``from __future__ import annotations``
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directive, which turns all annotations into strings. This directive is now
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considered deprecated and it is expected to be removed in a future version of Python.
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However, this removal will not happen until after Python 3.13, the last version of
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Python without deferred evaluation of annotations, reaches its end of life in 2029.
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In Python 3.14, the behavior of code using ``from __future__ import annotations``
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is unchanged.
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Improved error messages
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-----------------------
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* When unpacking assignment fails due to incorrect number of variables, the
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error message prints the received number of values in more cases than before.
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(Contributed by Tushar Sadhwani in :gh:`122239`.)
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.. code-block:: pycon
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>>> x, y, z = 1, 2, 3, 4
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Traceback (most recent call last):
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File "<stdin>", line 1, in <module>
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x, y, z = 1, 2, 3, 4
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^^^^^^^
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ValueError: too many values to unpack (expected 3, got 4)
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Other language changes
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======================
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* The :func:`map` built-in now has an optional keyword-only *strict* flag
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like :func:`zip` to check that all the iterables are of equal length.
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(Contributed by Wannes Boeykens in :gh:`119793`.)
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* Incorrect usage of :keyword:`await` and asynchronous comprehensions
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is now detected even if the code is optimized away by the :option:`-O`
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command-line option. For example, ``python -O -c 'assert await 1'``
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now produces a :exc:`SyntaxError`. (Contributed by Jelle Zijlstra in :gh:`121637`.)
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* Writes to ``__debug__`` are now detected even if the code is optimized
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away by the :option:`-O` command-line option. For example,
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``python -O -c 'assert (__debug__ := 1)'`` now produces a
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:exc:`SyntaxError`. (Contributed by Irit Katriel in :gh:`122245`.)
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* Add class methods :meth:`float.from_number` and :meth:`complex.from_number`
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to convert a number to :class:`float` or :class:`complex` type correspondingly.
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They raise an error if the argument is a string.
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(Contributed by Serhiy Storchaka in :gh:`84978`.)
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* All Windows code pages are now supported as "cpXXX" codecs on Windows.
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(Contributed by Serhiy Storchaka in :gh:`123803`.)
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* :class:`super` objects are now :mod:`pickleable <pickle>` and
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:mod:`copyable <copy>`.
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(Contributed by Serhiy Storchaka in :gh:`125767`.)
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* The :class:`memoryview` type now supports subscription,
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making it a :term:`generic type`.
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(Contributed by Brian Schubert in :gh:`126012`.)
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New modules
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===========
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* :mod:`annotationlib`: For introspecting :term:`annotations <annotation>`.
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See :pep:`749` for more details.
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(Contributed by Jelle Zijlstra in :gh:`119180`.)
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Improved modules
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================
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argparse
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--------
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* The default value of the :ref:`program name <prog>` for
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:class:`argparse.ArgumentParser` now reflects the way the Python
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interpreter was instructed to find the ``__main__`` module code.
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(Contributed by Serhiy Storchaka and Alyssa Coghlan in :gh:`66436`.)
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* Introduced the optional *suggest_on_error* parameter to
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:class:`argparse.ArgumentParser`, enabling suggestions for argument choices
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and subparser names if mistyped by the user.
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(Contributed by Savannah Ostrowski in :gh:`124456`.)
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ast
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---
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* Add :func:`ast.compare` for comparing two ASTs.
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(Contributed by Batuhan Taskaya and Jeremy Hylton in :gh:`60191`.)
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* Add support for :func:`copy.replace` for AST nodes.
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(Contributed by Bénédikt Tran in :gh:`121141`.)
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* Docstrings are now removed from an optimized AST in optimization level 2.
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(Contributed by Irit Katriel in :gh:`123958`.)
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* The ``repr()`` output for AST nodes now includes more information.
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(Contributed by Tomas R in :gh:`116022`.)
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concurrent.futures
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------------------
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* Add :class:`~concurrent.futures.InterpreterPoolExecutor`,
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which exposes "subinterpreters (multiple Python interpreters in the
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same process) to Python code. This is separate from the proposed API
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in :pep:`734`.
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(Contributed by Eric Snow in :gh:`124548`.)
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* The default ``ProcessPoolExecutor`` start method (see
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:ref:`multiprocessing-start-methods`) changed from *fork* to *forkserver* on
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platforms other than macOS & Windows. If you require the threading
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incompatible *fork* start method you must explicitly request it by
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supplying a *mp_context* to :class:`concurrent.futures.ProcessPoolExecutor`.
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(Contributed by Gregory P. Smith in :gh:`84559`.)
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ctypes
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------
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* The layout of :ref:`bit fields <ctypes-bit-fields-in-structures-unions>`
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in :class:`~ctypes.Structure` and :class:`~ctypes.Union`
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now matches platform defaults (GCC/Clang or MVSC) more closely.
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In particular, fields no longer overlap.
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(Contributed by Matthias Görgens in :gh:`97702`.)
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* The :attr:`.Structure._layout_` class attribute can now be set
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to help match a non-default ABI.
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(Contributed by Petr Viktorin in :gh:`97702`.)
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* The :exc:`~ctypes.COMError` exception is now public.
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(Contributed by Jun Komoda in :gh:`126686`.)
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datetime
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--------
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* Add :meth:`datetime.time.strptime` and :meth:`datetime.date.strptime`.
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(Contributed by Wannes Boeykens in :gh:`41431`.)
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decimal
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-------
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* Add alternative :class:`~decimal.Decimal` constructor
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:meth:`Decimal.from_number() <decimal.Decimal.from_number>`.
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(Contributed by Serhiy Storchaka in :gh:`121798`.)
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dis
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---
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* Add support for rendering full source location information of
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:class:`instructions <dis.Instruction>`, rather than only the line number.
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This feature is added to the following interfaces via the *show_positions*
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keyword argument:
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- :class:`dis.Bytecode`
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- :func:`dis.dis`
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- :func:`dis.distb`
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- :func:`dis.disassemble`
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This feature is also exposed via :option:`dis --show-positions`.
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(Contributed by Bénédikt Tran in :gh:`123165`.)
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fractions
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---------
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* Add support for converting any objects that have the
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:meth:`!as_integer_ratio` method to a :class:`~fractions.Fraction`.
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(Contributed by Serhiy Storchaka in :gh:`82017`.)
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* Add alternative :class:`~fractions.Fraction` constructor
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:meth:`Fraction.from_number() <fractions.Fraction.from_number>`.
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(Contributed by Serhiy Storchaka in :gh:`121797`.)
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functools
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---------
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* Add support to :func:`functools.partial` and
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:func:`functools.partialmethod` for :data:`functools.Placeholder` sentinels
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to reserve a place for positional arguments.
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(Contributed by Dominykas Grigonis in :gh:`119127`.)
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* Allow the *initial* parameter of :func:`functools.reduce` to be passed
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as a keyword argument.
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(Contributed by Sayandip Dutta in :gh:`125916`.)
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getopt
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------
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* Add support for options with optional arguments.
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(Contributed by Serhiy Storchaka in :gh:`126374`.)
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* Add support for returning intermixed options and non-option arguments in order.
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(Contributed by Serhiy Storchaka in :gh:`126390`.)
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http
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----
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* Directory lists and error pages generated by the :mod:`http.server`
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module allow the browser to apply its default dark mode.
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(Contributed by Yorik Hansen in :gh:`123430`.)
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inspect
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-------
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* :func:`inspect.signature` takes a new argument *annotation_format* to control
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the :class:`annotationlib.Format` used for representing annotations.
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(Contributed by Jelle Zijlstra in :gh:`101552`.)
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* :meth:`inspect.Signature.format` takes a new argument *unquote_annotations*.
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If true, string :term:`annotations <annotation>` are displayed without surrounding quotes.
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(Contributed by Jelle Zijlstra in :gh:`101552`.)
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* Add function :func:`inspect.ispackage` to determine whether an object is a
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:term:`package` or not.
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(Contributed by Zhikang Yan in :gh:`125634`.)
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json
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----
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* Add notes for JSON serialization errors that allow to identify the source
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of the error.
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(Contributed by Serhiy Storchaka in :gh:`122163`.)
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* Enable the :mod:`json` module to work as a script using the :option:`-m`
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switch: :program:`python -m json`.
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See the :ref:`JSON command-line interface <json-commandline>` documentation.
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(Contributed by Trey Hunner in :gh:`122873`.)
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mimetypes
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---------
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* Add MS and :rfc:`8081` MIME types for fonts:
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* Embedded OpenType: ``application/vnd.ms-fontobject``
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* OpenType Layout (OTF) ``font/otf``
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* TrueType: ``font/ttf``
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* WOFF 1.0 ``font/woff``
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* WOFF 2.0 ``font/woff2``
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(Contributed by Sahil Prajapati and Hugo van Kemenade in :gh:`84852`.)
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* Add :rfc:`9559` MIME types for Matroska audiovisual data container
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structures, containing:
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* audio with no video: ``audio/matroska`` (``.mka``)
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* video: ``video/matroska`` (``.mkv``)
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* stereoscopic video: ``video/matroska-3d`` (``.mk3d``)
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(Contributed by Hugo van Kemenade in :gh:`89416`.)
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* Add MIME types for images with RFCs:
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* :rfc:`1494`: CCITT Group 3 (``.g3``)
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* :rfc:`3362`: Real-time Facsimile, T.38 (``.t38``)
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* :rfc:`3745`: JPEG 2000 (``.jp2``), extension (``.jpx``) and compound (``.jpm``)
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* :rfc:`3950`: Tag Image File Format Fax eXtended, TIFF-FX (``.tfx``)
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* :rfc:`4047`: Flexible Image Transport System (``.fits``)
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* :rfc:`7903`: Enhanced Metafile (``.emf``) and Windows Metafile (``.wmf``)
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(Contributed by Hugo van Kemenade in :gh:`85957`.)
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multiprocessing
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---------------
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* The default start method (see :ref:`multiprocessing-start-methods`) changed
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from *fork* to *forkserver* on platforms other than macOS & Windows where
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it was already *spawn*. If you require the threading incompatible *fork*
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start method you must explicitly request it using a context from
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:func:`multiprocessing.get_context` (preferred) or change the default via
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:func:`multiprocessing.set_start_method`.
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(Contributed by Gregory P. Smith in :gh:`84559`.)
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* :mod:`multiprocessing`'s ``"forkserver"`` start method now authenticates
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its control socket to avoid solely relying on filesystem permissions
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to restrict what other processes could cause the forkserver to spawn workers
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and run code.
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(Contributed by Gregory P. Smith for :gh:`97514`.)
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* The :ref:`multiprocessing proxy objects <multiprocessing-proxy_objects>`
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for *list* and *dict* types gain previously overlooked missing methods:
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* :meth:`!clear` and :meth:`!copy` for proxies of :class:`list`.
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* :meth:`~dict.fromkeys`, ``reversed(d)``, ``d | {}``, ``{} | d``,
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``d |= {'b': 2}`` for proxies of :class:`dict`.
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(Contributed by Roy Hyunjin Han for :gh:`103134`.)
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operator
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--------
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* Two new functions :func:`operator.is_none` and :func:`operator.is_not_none`
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have been added, such that ``operator.is_none(obj)`` is equivalent
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to ``obj is None`` and ``operator.is_not_none(obj)`` is equivalent
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to ``obj is not None``.
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(Contributed by Raymond Hettinger and Nico Mexis in :gh:`115808`.)
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os
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--
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* Add the :func:`os.reload_environ` function to update :data:`os.environ` and
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:data:`os.environb` with changes to the environment made by
|
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:func:`os.putenv`, by :func:`os.unsetenv`, or made outside Python in the
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same process.
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(Contributed by Victor Stinner in :gh:`120057`.)
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pathlib
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-------
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* Add methods to :class:`pathlib.Path` to recursively copy or move files and
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directories:
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* :meth:`~pathlib.Path.copy` copies a file or directory tree to a destination.
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* :meth:`~pathlib.Path.copy_into` copies *into* a destination directory.
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* :meth:`~pathlib.Path.move` moves a file or directory tree to a destination.
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* :meth:`~pathlib.Path.move_into` moves *into* a destination directory.
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(Contributed by Barney Gale in :gh:`73991`.)
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* Add :meth:`pathlib.Path.scandir` to scan a directory and return an iterator
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of :class:`os.DirEntry` objects. This is exactly equivalent to calling
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:func:`os.scandir` on a path object.
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(Contributed by Barney Gale in :gh:`125413`.)
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pdb
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---
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* Hardcoded breakpoints (:func:`breakpoint` and :func:`pdb.set_trace`) now
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reuse the most recent :class:`~pdb.Pdb` instance that calls
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:meth:`~pdb.Pdb.set_trace`, instead of creating a new one each time.
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As a result, all the instance specific data like :pdbcmd:`display` and
|
|
:pdbcmd:`commands` are preserved across hardcoded breakpoints.
|
|
(Contributed by Tian Gao in :gh:`121450`.)
|
|
|
|
* Add a new argument *mode* to :class:`pdb.Pdb`. Disable the ``restart``
|
|
command when :mod:`pdb` is in ``inline`` mode.
|
|
(Contributed by Tian Gao in :gh:`123757`.)
|
|
|
|
platform
|
|
--------
|
|
|
|
* Add :func:`platform.invalidate_caches` to invalidate the cached results.
|
|
|
|
(Contributed by Bénédikt Tran in :gh:`122549`.)
|
|
|
|
|
|
pickle
|
|
------
|
|
|
|
* Set the default protocol version on the :mod:`pickle` module to 5.
|
|
For more details, see :ref:`pickle protocols <pickle-protocols>`.
|
|
|
|
* Add notes for pickle serialization errors that allow to identify the source
|
|
of the error.
|
|
(Contributed by Serhiy Storchaka in :gh:`122213`.)
|
|
|
|
pydoc
|
|
-----
|
|
|
|
* :term:`Annotations <annotation>` in help output are now usually
|
|
displayed in a format closer to that in the original source.
|
|
(Contributed by Jelle Zijlstra in :gh:`101552`.)
|
|
|
|
|
|
symtable
|
|
--------
|
|
|
|
* Expose the following :class:`symtable.Symbol` methods:
|
|
|
|
* :meth:`~symtable.Symbol.is_comp_cell`
|
|
* :meth:`~symtable.Symbol.is_comp_iter`
|
|
* :meth:`~symtable.Symbol.is_free_class`
|
|
|
|
(Contributed by Bénédikt Tran in :gh:`120029`.)
|
|
|
|
|
|
sys
|
|
---
|
|
|
|
* The previously undocumented special function :func:`sys.getobjects`,
|
|
which only exists in specialized builds of Python, may now return objects
|
|
from other interpreters than the one it's called in.
|
|
|
|
|
|
unicodedata
|
|
-----------
|
|
|
|
* The Unicode database has been updated to Unicode 16.0.0.
|
|
|
|
|
|
unittest
|
|
--------
|
|
|
|
* unittest discovery supports :term:`namespace package` as start
|
|
directory again. It was removed in Python 3.11.
|
|
(Contributed by Jacob Walls in :gh:`80958`.)
|
|
|
|
|
|
uuid
|
|
----
|
|
|
|
* Add support for UUID version 8 via :func:`uuid.uuid8` as specified
|
|
in :rfc:`9562`.
|
|
(Contributed by Bénédikt Tran in :gh:`89083`.)
|
|
|
|
|
|
.. Add improved modules above alphabetically, not here at the end.
|
|
|
|
Optimizations
|
|
=============
|
|
|
|
asyncio
|
|
-------
|
|
|
|
* :mod:`asyncio` now uses double linked list implementation for native tasks
|
|
which speeds up execution by 10% on standard pyperformance benchmarks and
|
|
reduces memory usage.
|
|
(Contributed by Kumar Aditya in :gh:`107803`.)
|
|
|
|
io
|
|
---
|
|
* :mod:`io` which provides the built-in :func:`open` makes less system calls
|
|
when opening regular files as well as reading whole files. Reading a small
|
|
operating system cached file in full is up to 15% faster.
|
|
:func:`pathlib.Path.read_bytes` has the most optimizations for reading a
|
|
file's bytes in full. (Contributed by Cody Maloney and Victor Stinner in
|
|
:gh:`120754` and :gh:`90102`.)
|
|
|
|
Deprecated
|
|
==========
|
|
|
|
* :mod:`argparse`:
|
|
|
|
* Passing the undocumented keyword argument *prefix_chars* to
|
|
:meth:`~argparse.ArgumentParser.add_argument_group` is now
|
|
deprecated.
|
|
(Contributed by Savannah Ostrowski in :gh:`125563`.)
|
|
* Deprecated the :class:`argparse.FileType` type converter.
|
|
Anything with resource management should be done downstream after the
|
|
arguments are parsed.
|
|
(Contributed by Serhiy Storchaka in :gh:`58032`.)
|
|
|
|
* :mod:`asyncio`:
|
|
:func:`!asyncio.iscoroutinefunction` is deprecated
|
|
and will be removed in Python 3.16,
|
|
use :func:`inspect.iscoroutinefunction` instead.
|
|
(Contributed by Jiahao Li and Kumar Aditya in :gh:`122875`.)
|
|
|
|
* :mod:`builtins`:
|
|
Passing a complex number as the *real* or *imag* argument in the
|
|
:func:`complex` constructor is now deprecated; it should only be passed
|
|
as a single positional argument.
|
|
(Contributed by Serhiy Storchaka in :gh:`109218`.)
|
|
|
|
* :mod:`os`:
|
|
:term:`Soft deprecate <soft deprecated>` :func:`os.popen` and
|
|
:func:`os.spawn* <os.spawnl>` functions. They should no longer be used to
|
|
write new code. The :mod:`subprocess` module is recommended instead.
|
|
(Contributed by Victor Stinner in :gh:`120743`.)
|
|
|
|
* :mod:`symtable`:
|
|
Deprecate :meth:`symtable.Class.get_methods` due to the lack of interest.
|
|
(Contributed by Bénédikt Tran in :gh:`119698`.)
|
|
|
|
* :mod:`urllib.parse`:
|
|
Accepting objects with false values (like ``0`` and ``[]``) except empty
|
|
strings, byte-like objects and ``None`` in :mod:`urllib.parse` functions
|
|
:func:`~urllib.parse.parse_qsl` and :func:`~urllib.parse.parse_qs` is now
|
|
deprecated.
|
|
(Contributed by Serhiy Storchaka in :gh:`116897`.)
|
|
|
|
.. Add deprecations above alphabetically, not here at the end.
|
|
|
|
.. include:: ../deprecations/pending-removal-in-3.15.rst
|
|
|
|
.. include:: ../deprecations/pending-removal-in-3.16.rst
|
|
|
|
.. include:: ../deprecations/pending-removal-in-future.rst
|
|
|
|
Removed
|
|
=======
|
|
|
|
argparse
|
|
--------
|
|
|
|
* Remove the *type*, *choices*, and *metavar* parameters
|
|
of :class:`!argparse.BooleanOptionalAction`.
|
|
They were deprecated since 3.12.
|
|
|
|
ast
|
|
---
|
|
|
|
* Remove the following classes. They were all deprecated since Python 3.8,
|
|
and have emitted deprecation warnings since Python 3.12:
|
|
|
|
* :class:`!ast.Bytes`
|
|
* :class:`!ast.Ellipsis`
|
|
* :class:`!ast.NameConstant`
|
|
* :class:`!ast.Num`
|
|
* :class:`!ast.Str`
|
|
|
|
Use :class:`ast.Constant` instead. As a consequence of these removals,
|
|
user-defined ``visit_Num``, ``visit_Str``, ``visit_Bytes``,
|
|
``visit_NameConstant`` and ``visit_Ellipsis`` methods on custom
|
|
:class:`ast.NodeVisitor` subclasses will no longer be called when the
|
|
:class:`!NodeVisitor` subclass is visiting an AST. Define a ``visit_Constant``
|
|
method instead.
|
|
|
|
Also, remove the following deprecated properties on :class:`ast.Constant`,
|
|
which were present for compatibility with the now-removed AST classes:
|
|
|
|
* :attr:`!ast.Constant.n`
|
|
* :attr:`!ast.Constant.s`
|
|
|
|
Use :attr:`!ast.Constant.value` instead.
|
|
|
|
(Contributed by Alex Waygood in :gh:`119562`.)
|
|
|
|
asyncio
|
|
-------
|
|
|
|
* Remove the following classes and functions. They were all deprecated and
|
|
emitted deprecation warnings since Python 3.12:
|
|
|
|
* :func:`!asyncio.get_child_watcher`
|
|
* :func:`!asyncio.set_child_watcher`
|
|
* :meth:`!asyncio.AbstractEventLoopPolicy.get_child_watcher`
|
|
* :meth:`!asyncio.AbstractEventLoopPolicy.set_child_watcher`
|
|
* :class:`!asyncio.AbstractChildWatcher`
|
|
* :class:`!asyncio.FastChildWatcher`
|
|
* :class:`!asyncio.MultiLoopChildWatcher`
|
|
* :class:`!asyncio.PidfdChildWatcher`
|
|
* :class:`!asyncio.SafeChildWatcher`
|
|
* :class:`!asyncio.ThreadedChildWatcher`
|
|
|
|
(Contributed by Kumar Aditya in :gh:`120804`.)
|
|
|
|
* Removed implicit creation of event loop by :func:`asyncio.get_event_loop`.
|
|
It now raises a :exc:`RuntimeError` if there is no current event loop.
|
|
(Contributed by Kumar Aditya in :gh:`126353`.)
|
|
|
|
|
|
collections.abc
|
|
---------------
|
|
|
|
* Remove :class:`!collections.abc.ByteString`. It had previously raised a
|
|
:exc:`DeprecationWarning` since Python 3.12.
|
|
|
|
email
|
|
-----
|
|
|
|
* Remove the *isdst* parameter from :func:`email.utils.localtime`.
|
|
(Contributed by Hugo van Kemenade in :gh:`118798`.)
|
|
|
|
importlib
|
|
---------
|
|
|
|
* Remove deprecated :mod:`importlib.abc` classes:
|
|
|
|
* :class:`!importlib.abc.ResourceReader`
|
|
* :class:`!importlib.abc.Traversable`
|
|
* :class:`!importlib.abc.TraversableResources`
|
|
|
|
Use :mod:`importlib.resources.abc` classes instead:
|
|
|
|
* :class:`importlib.resources.abc.Traversable`
|
|
* :class:`importlib.resources.abc.TraversableResources`
|
|
|
|
(Contributed by Jason R. Coombs and Hugo van Kemenade in :gh:`93963`.)
|
|
|
|
itertools
|
|
---------
|
|
|
|
* Remove :mod:`itertools` support for copy, deepcopy, and pickle operations.
|
|
These had previously raised a :exc:`DeprecationWarning` since Python 3.12.
|
|
(Contributed by Raymond Hettinger in :gh:`101588`.)
|
|
|
|
pathlib
|
|
-------
|
|
|
|
* Remove support for passing additional keyword arguments to
|
|
:class:`pathlib.Path`. In previous versions, any such arguments are ignored.
|
|
* Remove support for passing additional positional arguments to
|
|
:meth:`pathlib.PurePath.relative_to` and
|
|
:meth:`~pathlib.PurePath.is_relative_to`. In previous versions, any such
|
|
arguments are joined onto *other*.
|
|
|
|
pkgutil
|
|
-------
|
|
|
|
* Remove deprecated :func:`!pkgutil.get_loader` and :func:`!pkgutil.find_loader`.
|
|
These had previously raised a :exc:`DeprecationWarning` since Python 3.12.
|
|
(Contributed by Bénédikt Tran in :gh:`97850`.)
|
|
|
|
pty
|
|
---
|
|
|
|
* Remove deprecated :func:`!pty.master_open` and :func:`!pty.slave_open`.
|
|
They had previously raised a :exc:`DeprecationWarning` since Python 3.12.
|
|
Use :func:`pty.openpty` instead.
|
|
(Contributed by Nikita Sobolev in :gh:`118824`.)
|
|
|
|
sqlite3
|
|
-------
|
|
|
|
* Remove :data:`!version` and :data:`!version_info` from :mod:`sqlite3`.
|
|
(Contributed by Hugo van Kemenade in :gh:`118924`.)
|
|
|
|
* Disallow using a sequence of parameters with named placeholders.
|
|
This had previously raised a :exc:`DeprecationWarning` since Python 3.12;
|
|
it will now raise a :exc:`sqlite3.ProgrammingError`.
|
|
(Contributed by Erlend E. Aasland in :gh:`118928` and :gh:`101693`.)
|
|
|
|
typing
|
|
------
|
|
|
|
* Remove :class:`!typing.ByteString`. It had previously raised a
|
|
:exc:`DeprecationWarning` since Python 3.12.
|
|
|
|
urllib
|
|
------
|
|
|
|
* Remove deprecated :class:`!Quoter` class from :mod:`urllib.parse`.
|
|
It had previously raised a :exc:`DeprecationWarning` since Python 3.11.
|
|
(Contributed by Nikita Sobolev in :gh:`118827`.)
|
|
* Remove deprecated :class:`!URLopener` and :class:`!FancyURLopener` classes
|
|
from :mod:`urllib.request`. They had previously raised a
|
|
:exc:`DeprecationWarning` since Python 3.3.
|
|
|
|
``myopener.open()`` can be replaced with :func:`~urllib.request.urlopen`,
|
|
and ``myopener.retrieve()`` can be replaced with
|
|
:func:`~urllib.request.urlretrieve`. Customizations to the opener
|
|
classes can be replaced by passing customized handlers to
|
|
:func:`~urllib.request.build_opener`.
|
|
|
|
(Contributed by Barney Gale in :gh:`84850`.)
|
|
|
|
Others
|
|
------
|
|
|
|
* Using :data:`NotImplemented` in a boolean context will now raise a :exc:`TypeError`.
|
|
It had previously raised a :exc:`DeprecationWarning` since Python 3.9. (Contributed
|
|
by Jelle Zijlstra in :gh:`118767`.)
|
|
|
|
* The :func:`int` built-in no longer delegates to
|
|
:meth:`~object.__trunc__`. Classes that want to support conversion to
|
|
integer must implement either :meth:`~object.__int__` or
|
|
:meth:`~object.__index__`. (Contributed by Mark Dickinson in :gh:`119743`.)
|
|
|
|
|
|
Porting to Python 3.14
|
|
======================
|
|
|
|
This section lists previously described changes and other bugfixes
|
|
that may require changes to your code.
|
|
|
|
Changes in the Python API
|
|
-------------------------
|
|
|
|
* :class:`functools.partial` is now a method descriptor.
|
|
Wrap it in :func:`staticmethod` if you want to preserve the old behavior.
|
|
(Contributed by Serhiy Storchaka and Dominykas Grigonis in :gh:`121027`.)
|
|
|
|
* The :func:`locale.nl_langinfo` function now sets temporarily the ``LC_CTYPE``
|
|
locale in some cases.
|
|
This temporary change affects other threads.
|
|
(Contributed by Serhiy Storchaka in :gh:`69998`.)
|
|
|
|
|
|
Build changes
|
|
=============
|
|
|
|
PEP 761: Discontinuation of PGP signatures
|
|
------------------------------------------
|
|
|
|
PGP signatures will not be available for CPython 3.14 and onwards.
|
|
Users verifying artifacts must use `Sigstore verification materials`_ for
|
|
verifying CPython artifacts. This change in release process is specified
|
|
in :pep:`761`.
|
|
|
|
.. _Sigstore verification materials: https://www.python.org/downloads/metadata/sigstore/
|
|
|
|
|
|
C API changes
|
|
=============
|
|
|
|
New features
|
|
------------
|
|
|
|
* Add :c:func:`PyLong_GetSign` function to get the sign of :class:`int` objects.
|
|
(Contributed by Sergey B Kirpichev in :gh:`116560`.)
|
|
|
|
* Add a new :c:type:`PyUnicodeWriter` API to create a Python :class:`str`
|
|
object:
|
|
|
|
* :c:func:`PyUnicodeWriter_Create`
|
|
* :c:func:`PyUnicodeWriter_DecodeUTF8Stateful`
|
|
* :c:func:`PyUnicodeWriter_Discard`
|
|
* :c:func:`PyUnicodeWriter_Finish`
|
|
* :c:func:`PyUnicodeWriter_Format`
|
|
* :c:func:`PyUnicodeWriter_WriteChar`
|
|
* :c:func:`PyUnicodeWriter_WriteRepr`
|
|
* :c:func:`PyUnicodeWriter_WriteStr`
|
|
* :c:func:`PyUnicodeWriter_WriteSubstring`
|
|
* :c:func:`PyUnicodeWriter_WriteUCS4`
|
|
* :c:func:`PyUnicodeWriter_WriteUTF8`
|
|
* :c:func:`PyUnicodeWriter_WriteWideChar`
|
|
|
|
(Contributed by Victor Stinner in :gh:`119182`.)
|
|
|
|
* Add :c:func:`PyIter_NextItem` to replace :c:func:`PyIter_Next`,
|
|
which has an ambiguous return value.
|
|
(Contributed by Irit Katriel and Erlend Aasland in :gh:`105201`.)
|
|
|
|
* :c:func:`Py_Finalize` now deletes all interned strings. This
|
|
is backwards incompatible to any C-Extension that holds onto an interned
|
|
string after a call to :c:func:`Py_Finalize` and is then reused after a
|
|
call to :c:func:`Py_Initialize`. Any issues arising from this behavior will
|
|
normally result in crashes during the execution of the subsequent call to
|
|
:c:func:`Py_Initialize` from accessing uninitialized memory. To fix, use
|
|
an address sanitizer to identify any use-after-free coming from
|
|
an interned string and deallocate it during module shutdown.
|
|
(Contributed by Eddie Elizondo in :gh:`113601`.)
|
|
|
|
* Add :c:func:`PyLong_IsPositive`, :c:func:`PyLong_IsNegative`
|
|
and :c:func:`PyLong_IsZero` for checking if :c:type:`PyLongObject`
|
|
is positive, negative, or zero, respectively.
|
|
(Contributed by James Roy and Sergey B Kirpichev in :gh:`126061`.)
|
|
|
|
* Add new functions to convert C ``<stdint.h>`` numbers from/to Python
|
|
:class:`int`:
|
|
|
|
* :c:func:`PyLong_AsInt32`
|
|
* :c:func:`PyLong_AsInt64`
|
|
* :c:func:`PyLong_AsUInt32`
|
|
* :c:func:`PyLong_AsUInt64`
|
|
* :c:func:`PyLong_FromInt32`
|
|
* :c:func:`PyLong_FromInt64`
|
|
* :c:func:`PyLong_FromUInt32`
|
|
* :c:func:`PyLong_FromUInt64`
|
|
|
|
(Contributed by Victor Stinner in :gh:`120389`.)
|
|
|
|
* Add :c:func:`PyBytes_Join(sep, iterable) <PyBytes_Join>` function,
|
|
similar to ``sep.join(iterable)`` in Python.
|
|
(Contributed by Victor Stinner in :gh:`121645`.)
|
|
|
|
* Add :c:func:`Py_HashBuffer` to compute and return the hash value of a buffer.
|
|
(Contributed by Antoine Pitrou and Victor Stinner in :gh:`122854`.)
|
|
|
|
* Add functions to get and set the current runtime Python configuration
|
|
(:pep:`741`):
|
|
|
|
* :c:func:`PyConfig_Get`
|
|
* :c:func:`PyConfig_GetInt`
|
|
* :c:func:`PyConfig_Set`
|
|
* :c:func:`PyConfig_Names`
|
|
|
|
(Contributed by Victor Stinner in :gh:`107954`.)
|
|
|
|
* Add functions to configure the Python initialization (:pep:`741`):
|
|
|
|
* :c:func:`Py_InitializeFromInitConfig`
|
|
* :c:func:`PyInitConfig_AddModule`
|
|
* :c:func:`PyInitConfig_Create`
|
|
* :c:func:`PyInitConfig_Free`
|
|
* :c:func:`PyInitConfig_FreeStrList`
|
|
* :c:func:`PyInitConfig_GetError`
|
|
* :c:func:`PyInitConfig_GetExitCode`
|
|
* :c:func:`PyInitConfig_GetInt`
|
|
* :c:func:`PyInitConfig_GetStr`
|
|
* :c:func:`PyInitConfig_GetStrList`
|
|
* :c:func:`PyInitConfig_HasOption`
|
|
* :c:func:`PyInitConfig_SetInt`
|
|
* :c:func:`PyInitConfig_SetStr`
|
|
* :c:func:`PyInitConfig_SetStrList`
|
|
|
|
(Contributed by Victor Stinner in :gh:`107954`.)
|
|
|
|
* Add :c:func:`PyType_GetBaseByToken` and :c:data:`Py_tp_token` slot for easier
|
|
superclass identification, which attempts to resolve the `type checking issue
|
|
<https://peps.python.org/pep-0630/#type-checking>`__ mentioned in :pep:`630`
|
|
(:gh:`124153`).
|
|
|
|
* Add :c:func:`PyUnicode_Equal` function to the limited C API:
|
|
test if two strings are equal.
|
|
(Contributed by Victor Stinner in :gh:`124502`.)
|
|
|
|
|
|
* Add :c:func:`PyType_Freeze` function to make a type immutable.
|
|
(Contributed by Victor Stinner in :gh:`121654`.)
|
|
|
|
* Add :c:func:`PyUnstable_Object_EnableDeferredRefcount` for enabling
|
|
deferred reference counting, as outlined in :pep:`703`.
|
|
|
|
Porting to Python 3.14
|
|
----------------------
|
|
|
|
* In the limited C API 3.14 and newer, :c:func:`Py_TYPE` and
|
|
:c:func:`Py_REFCNT` are now implemented as an opaque function call to hide
|
|
implementation details.
|
|
(Contributed by Victor Stinner in :gh:`120600` and :gh:`124127`.)
|
|
|
|
|
|
Deprecated
|
|
----------
|
|
|
|
* The :c:macro:`!Py_HUGE_VAL` macro is :term:`soft deprecated`,
|
|
use :c:macro:`!Py_INFINITY` instead.
|
|
(Contributed by Sergey B Kirpichev in :gh:`120026`.)
|
|
|
|
* Macros :c:macro:`!Py_IS_NAN`, :c:macro:`!Py_IS_INFINITY`
|
|
and :c:macro:`!Py_IS_FINITE` are :term:`soft deprecated`,
|
|
use instead :c:macro:`!isnan`, :c:macro:`!isinf` and
|
|
:c:macro:`!isfinite` available from :file:`math.h`
|
|
since C99. (Contributed by Sergey B Kirpichev in :gh:`119613`.)
|
|
|
|
.. Add C API deprecations above alphabetically, not here at the end.
|
|
|
|
.. include:: ../deprecations/c-api-pending-removal-in-3.15.rst
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.. include:: ../deprecations/c-api-pending-removal-in-future.rst
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Removed
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-------
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* Creating :c:data:`immutable types <Py_TPFLAGS_IMMUTABLETYPE>` with mutable
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bases was deprecated since 3.12 and now raises a :exc:`TypeError`.
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