Python 3.13 有什么新变化
************************

Editors:
   Adam Turner and Thomas Wouters

本文介绍了 Python 3.13 相比 3.12 增加的新特性。 Python 3.13 将于 2024
年 10 月 1 日发布。 要获取详细信息，可参阅 changelog。

参见: **PEP 719** -- Python 3.13 发布计划


摘要 -- 发布重点
================

Python 3.13 将是 Python 编程语言的最新稳定发布版，包含多项针对语言、实
现和标准库的改变。 最大的变化包括一个新的 交互式解释器，以及对于在 自
由线程模式 (**PEP 703**) 下运行和 即时编译器 (**PEP 744**) 的实验性支
持。

错误消息继续得到改进，回溯信息现在默认使用彩色高亮显示。 "locals()" 内
置函数现在对于修改所返回的映射具有 更细化的语法，并且类型形参现在支持
设置默认值。

针对标准库的改变包括移除已弃用的 API 和模块，以及用户友好度和正确性方
面的常规提升。 一些旧式标准库模块自 Python 3.11 起被弃用 (**PEP 594**)
之后现在 已被移除。

本文并不试图提供所有新特性的完整规范说明，而是提供一个方便的概览。 要
了解完整细节请参阅相应文档，如 标准库参数 和 语言参考。 要了解某项改变
的完整实现和设计理念，请参阅相应新特性的 PEP；但请注意一旦某项特性已完
全实现则相应 PEP 通常不会再继续更新。 请参阅 迁移到 Python 3.13 了解如
何从较早 Python 进行升级的指导。

======================================================================

解释器的改进：

* 大幅改进的 交互式解释器 和 改进的错误消息。

* **PEP 667**: 现在 "locals()" 内置函数在修改被返回的映射时具有 已定义
  语义。 Python 调试器及类似的工具现在即使在并发代码执行期间也能更可靠
  地在已优化的作用域中更新局部变量。

* **PEP 703**: CPython 3.13 具有对在运行时禁用 *global interpreter
  lock* 的实验性支持。 请参阅 自由线程 CPython 了解详情。

* **PEP 744**: 增加了一个基本的 JIT 编译器。 目前默认是禁用的（但以后
  可能启用）。 能够小幅提升性能 -- 我们预计在接下来的几个发布版中不断
  改进它。

* 在新的 交互式解释器 中，以及 回溯信息 和 文档测试 输出中的颜色支持。
  这可以通过 "PYTHON_COLORS" and "NO_COLOR" 环境变量来禁用。

对 Python 数据模型的改进：

* "__static_attributes__" 存储了可在一个类体的任何函数中通过 "self.X"
  来访问的属性名称。

* "__firstlineno__" 记录了一个类定义的首行的行号。

标准库中的重大改进：

* 新增了 "PythonFinalizationError" 异常，当操作在 *最终化* 期间被阻塞
  时将被引发。

* 现在 "argparse" 模块可支持弃用命令行选项、位置参数和子命令。

* 新增的函数 "base64.z85encode()" 和 "base64.z85decode()" 支持对 Z85
  数据 进行编码和解码。

* 现在 "copy" 模块有一个 "copy.replace()" 函数，支持许多内置类型和任何
  定义了 "__replace__()" 方法的类。

* The new "dbm.sqlite3" module is now the default "dbm" backend.

* "os" 模块增加了 一套新函数 用于处理 Linux 的定时器通知文件描述符。

* 现在 "random" 模块提供了一个 命令行界面。

安全改进：

* "ssl.create_default_context()" 设置了
  "ssl.VERIFY_X509_PARTIAL_CHAIN" 和 "ssl.VERIFY_X509_STRICT" 作为默认
  的旗标。

C API 的改进：

* 现在 "Py_mod_gil" 槽位被用来指明一个扩展模块支持在禁用 *GIL* 的情况
  下运行。

* 增加了 PyTime C API，提供了对系统时钟的访问。

* "PyMutex" 是新增的轻量级互斥锁，只占用一个字节。

* There is a new suite of functions for generating **PEP 669**
  monitoring events in the C API.

新的类型标注特性：

* **PEP 696**: 类型形参 ("typing.TypeVar", "typing.ParamSpec" 和
  "typing.TypeVarTuple") 现在可支持默认值。

* **PEP 702**: The new "warnings.deprecated()" decorator adds support
  for marking deprecations in the type system and at runtime.

* **PEP 705**: "typing.ReadOnly" 可被用来将 "typing.TypedDict" 的项标
  记为对类型检查器只读。

* **PEP 742**: "typing.TypeIs" 提供了更直观的类型细化行为，作为对
  "typing.TypeGuard" 的替代。

平台支持：

* **PEP 730**: Apple's iOS is now an officially supported platform, at
  **tier 3**.

* **PEP 738**: Android is now an officially supported platform, at
  **tier 3**.

* 现在 "wasm32-wasi" 作为 **第 2 层级** 的平台受到支持。

* "wasm32-emscripten" 不再是受到官方支持的平台。

重要的移除：

* PEP 594: The remaining 19 "dead batteries" (legacy stdlib modules)
  have been removed from the standard library: "aifc", "audioop",
  "cgi", "cgitb", "chunk", "crypt", "imghdr", "mailcap", "msilib",
  "nis", "nntplib", "ossaudiodev", "pipes", "sndhdr", "spwd", "sunau",
  "telnetlib", "uu" and "xdrlib".

* 移除了 **2to3** 工具和 "lib2to3" 模块（在 Python 3.11 中已被弃用）。

* 移除了 "tkinter.tix" 模块（在 Python 3.6 中已被弃用）。

* Remove the "locale.resetlocale()" function.

* Remove the "typing.io" and "typing.re" namespaces.

* 移除了链式的 "classmethod" 描述器。

发布计划的变化：

**PEP 602** ("Annual Release Cycle for Python") 已被更新为将新发布版的
完整支持 ('bugfix') 期扩展至两年。 这个更新的政策意味着：

* Python 3.9--3.12 有一年半的完整支持，另加三年半的安全修正。

* Python 3.13 及以后的版本有两年的完整支持，另加三年的安全修正。


新的特性
========


更好的交互式解释器
------------------

Python 现在默认会使用新的 *interactive* shell，它基于来自 PyPy 项目 的
代码。 当使用从交互式终端启动 *REPL* 时，下列新特性将受到支持：

* 多行编辑并保留历史记录。

* 对 REPL 专属的命令如 "help", "exit" 和 "quit" 的直接支持，无需以函数
  形式调用它们。

* 提示和回溯 默认启用彩色显示。

* 使用 "F1" 浏览交互式帮助并带有单独的命令历史。

* 使用 "F2" 浏览去除了输出以及 *>>>* 和 *...* 提示符的历史。

* 使用 "F3" 进入“粘贴模式”以更方便地粘贴大段代码（再次按 "F3" 返回常规
  提示符）。

要禁用新的交互式 shell，可设置 "PYTHON_BASIC_REPL" 环境变量。 有关交互
模式的详情，请参见 交互模式。

（由 Pablo Galindo Salgado, Łukasz Langa 和 Lysandros Nikolaou 在
gh-111201 基于来自 PyPy 项目的代码贡献。 Windows 支持由 Dino Viehland
和 Anthony Shaw 贡献。）


改进的错误消息
--------------

* 在终端里显示回溯时解释器现在会默认使用彩色。 此特性可通过新的
  "PYTHON_COLORS" 环境变量以及传统的 "NO_COLOR" 和 "FORCE_COLOR" 环境
  变量来 进行控制。 （由 Pablo Galindo Salgado 在 gh-112730 中贡献。）

* 一个常见错误是撰写的脚本和标准库中的某个模块重名。现在出现此类错误时
  会显示一条更有用的错误信息：

     $ python random.py
     Traceback (most recent call last):
       File "/home/me/random.py", line 1, in <module>
         import random
       File "/home/me/random.py", line 3, in <module>
         print(random.randint(5))
               ^^^^^^^^^^^^^^
     AttributeError: module 'random' has no attribute 'randint' (consider renaming '/home/me/random.py' since it has the same name as the standard library module named 'random' and the import system gives it precedence)

  类似地，如果一个脚本具有与它尝试导入的第三方模块相同的名称并因此导致
  错误，我们也会显示一条更有帮助的错误消息：

     $ python numpy.py
     Traceback (most recent call last):
       File "/home/me/numpy.py", line 1, in <module>
         import numpy as np
       File "/home/me/numpy.py", line 3, in <module>
         np.array([1, 2, 3])
         ^^^^^^^^
     AttributeError: module 'numpy' has no attribute 'array' (consider renaming '/home/me/numpy.py' if it has the same name as a third-party module you intended to import)

  (由 Shantanu Jain 在 gh-95754 中贡献）。

* 现在当向一个函数传入不正确的关键字参数时错误消息会尝试提示正确的关键
  字参数。

     >>> "Better error messages!".split(max_split=1)
     Traceback (most recent call last):
       File "<python-input-0>", line 1, in <module>
         "Better error messages!".split(max_split=1)
         ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^
     TypeError: split() got an unexpected keyword argument 'max_split'. Did you mean 'maxsplit'?

  （由 Pablo Galindo Salgado 和 Shantanu Jain 在 gh-107944 中贡献。）


自由线程的 CPython
------------------

现在 CPython 具有对运行于自由线程模式的实验性支持，即禁用 *global
interpreter lock* (GIL)。 这是一个实验性的特性因而默认是不启用的。 自
由线程模式需要一个不同的可执行程序，通常名为 "python3.13t" 或
"python3.13t.exe"。 标记为 *自由线程* 的预构建二进制文件可作为官方
Windows 和 macOS 安装器的一部分被安装，或者可以附带 "--disable-gil" 选
项使用源代码来构建 CPython。

Free-threaded execution allows for full utilization of the available
processing power by running threads in parallel on available CPU
cores. While not all software will benefit from this automatically,
programs designed with threading in mind will run faster on multi-core
hardware. **The free-threaded mode is experimental** and work is
ongoing to improve it: expect some bugs and a substantial single-
threaded performance hit. Free-threaded builds of CPython support
optionally running with the GIL enabled at runtime using the
environment variable "PYTHON_GIL" or the command-line option "-X
gil=1".

为了检查当前解释器是否支持自由线程，"python -VV" 和 "sys.version" 将包
含 "experimental free-theading build" 字样。 可以使用新增的
"sys._is_gil_enabled()" 函数来检查正在运行的线程是否确实禁用了 GIL。

C-API 扩展模块需要针对自由线程构建版专门进行构建。 支持在禁用 *GIL* 的
情况下运行的扩展应当使用 "Py_mod_gil" 槽位。 使用单阶段初始化的扩展应
当使用 "PyUnstable_Module_SetGIL()" 来指明它们是支支持在禁用 GIL 的情
况下运行。 导入不使用这些机制的 C 扩展将导致 GIL 被启用，除非通过
"PYTHON_GIL" 环境变量或 "-X gil=0" 选项显式地禁用 GIL。 需要 pip 24.1
或更新的版本才能在自由线程构建版中安装带有 C 扩展的软件包。

This work was made possible thanks to many individuals and
organizations, including the large community of contributors to Python
and third-party projects to test and enable free-threading support.
Notable contributors include: Sam Gross, Ken Jin, Donghee Na, Itamar
Oren, Matt Page, Brett Simmers, Dino Viehland, Carl Meyer, Nathan
Goldbaum, Ralf Gommers, Lysandros Nikolaou, and many others. Many of
these contributors are employed by Meta, which has provided
significant engineering resources to support this project.

参见:

  **PEP 703** "Making the Global Interpreter Lock Optional in CPython"
  中包含了有关此项工作的理念和信息。

  Porting Extension Modules to Support Free-Threading: 一份由社区维护
  的针对扩展开发者的移植指南。


实验性的即时 (JIT) 编译器
-------------------------

当 CPython 使用 "--enable-experimental-jit" 选项进行配置和构建时，会添
加一个即时（JIT）编译器以加快某些 Python 程序的运行速度。 在 Windows
上，可使用 "PCbuild/build.bat --experimental-jit" 启用 JIT 或使用 "--
experimental-jit-interpreter" 启用第 2 层级解释器。 构建要求和进一步的
支持信息 包含在 "Tools/jit/README.md" 中。

"--enable-experimental-jit" 选项接受这些（可选）值，如果不带可选值地预
设 "--enable-experimental-jit" 则默认为 "yes"。

* "no": 禁用整个第 2 层级和 JIT 管线。

* "yes": 启用 JIT。 要在运行时禁用 JIT，则传入环境变量 "PYTHON_JIT=0"
  。

* "yes-off": 构建 JIT 但默认禁用它。 要在运行时启用 JIT，则传入环境变
  量 "PYTHON_JIT=1"。

* "interpreter": 启用第 2 层级解释器但是禁用 JIT。 可以在运行时传入
  "PYTHON_JIT=0" 来禁用该解释器。

其内部架构大致如下：

* 我们将从特化的 *第 1 层级字节码* 开始。 请参阅 3.11 有什么新变化 了
  解详情。

* 当第 1 层级字节码达到足够热度，它将被翻译为新的纯内部的中间表示形式
  (IR)，称为 *第 2 层级 IR*，有时也称为微操作码 ("uops")。

* 第 2 层级 IR 使用与第 1 层级相同的基于栈的虚拟机，但其指令格式更适合
  被翻译为机器码。

* 在第 2 层级 IR 被解释或翻译为机器码之前，我们会预先应用一些优化通路
  。

* 虽然第 2 层级解释器存在，但它主要用于对优化管线的先前阶段进行调试。
  可通过为 Python 配置 "--enable-experimental-jit=interpreter" 选项启
  用第 2 层级解释器。

* 启用 JIT 时，经优化的第 2 层级 IR 将被翻译为机器码后再执行。

* 这个机器码翻译过程使用了名为 *拷贝并打补丁* 的技巧。 它没有运行时依
  赖，但增加了构建时对 LLVM 的依赖。

参见: **PEP 744**

（JIT 来自 Brandt Bucher 且受到 Haoran Xu 和 Fredrik Kjolstad 论文的启
发。第 2 层级 IR 来自 Mark Shannon 和 Guido van Rossum。第 2 层级解释
器来自 Ken Jin。）


针对 "locals()" 的已定义修改语义
--------------------------------

Historically, the expected result of mutating the return value of
"locals()" has been left to individual Python implementations to
define. Starting from Python 3.13, **PEP 667** standardises the
historical behavior of CPython for most code execution scopes, but
changes *optimized scopes* (functions, generators, coroutines,
comprehensions, and generator expressions) to explicitly return
independent snapshots of the currently assigned local variables,
including locally referenced nonlocal variables captured in closures.

This change to the semantics of "locals()" in optimized scopes also
affects the default behavior of code execution functions that
implicitly target "locals()" if no explicit namespace is provided
(such as "exec()" and "eval()"). In previous versions, whether or not
changes could be accessed by calling "locals()" after calling the code
execution function was implementation-dependent. In CPython
specifically, such code would typically appear to work as desired, but
could sometimes fail in optimized scopes based on other code
(including debuggers and code execution tracing tools) potentially
resetting the shared snapshot in that scope. Now, the code will always
run against an independent snapshot of the local variables in
optimized scopes, and hence the changes will never be visible in
subsequent calls to "locals()". To access the changes made in these
cases, an explicit namespace reference must now be passed to the
relevant function. Alternatively, it may make sense to update affected
code to use a higher level code execution API that returns the
resulting code execution namespace (e.g. "runpy.run_path()" when
executing Python files from disk).

为确保调试器和类似工具能可靠地更新受到此变化影响的作用域中的局部变量，
现在 "FrameType.f_locals" 将返回一个针对此种作用域中的帧的局部变量和在
局部引用的非局部变量的直通写入代理对象，而不是返回一个非持续更新的具有
规定义的运行时语义的共享 "dict" 实例。

请参阅 **PEP 667** 了解详情，包括相关的 C API 更改和弃用。 下文还针对
受影响的 Python API 和 C API 提供了移植说明。

（PEP 和实现由 Mark Shannon 和 Tian Gao 在 gh-74929 中贡献。 文档更新
由 Guido van Rossum 和 Alyssa Coghlan 提供。）


对移动平台的支持
----------------

**PEP 730**: iOS 现在是 **PEP 11** 所支持的平台，包括第 3 层级的
"arm64-apple-ios" 和 "arm64-apple-ios-simulator" 等目标（分别为2013 年
后的 iPhone 和 iPad 设备以及运行于 Apple silicon 硬件的 Xcode iOS 模拟
器）。 "x86_64-apple-ios-simulator" （运行于较旧的 "x86_64" 硬件的
Xcode iOS 模拟器）不是第 3 层级的受支持平台，但也将尽可能地支持。 （
PEP 撰写及实现由 Russell Keith-Magee 在 gh-114099 中贡献。）.)

**PEP 738**: Android is now a **PEP 11** supported platform, with the
"aarch64-linux-android" and "x86_64-linux-android" targets at tier 3.
The 32-bit targets "arm-linux-androideabi" and "i686-linux-android"
are not tier 3 supported platforms, but will have best-effort support.
(PEP written and implementation contributed by Malcolm Smith in
gh-116622.)

参见: **PEP 730**, **PEP 738**


增量式垃圾回收
--------------

循环垃圾回收器现在是增量式的。这意味着对更大的堆进行垃圾收集的最大暂停
时间会减小一个数量级以上。

现在只分两代：新的和老的。 当 "gc.collect()" 不是被直接调用时，GC 被发
起调用的频次将略微减少。 当被发起调用时，它会回收新的一代并累加老的一
代，而不是回收一代或多代。

"gc.collect()" 的行为略有变化：

* "gc.collect(1)": Performs an increment of garbage collection, rather
  than collecting generation 1.

* 其他对 "gc.collect()" 的调用没有变化。

（由 Mark Shannon 在 gh-108362 中贡献。）


其他语言特性修改
================

* 编译器现在将从文档字符串的每一行去除共有的前导空格。 这会减少 *字节
  码缓存* 的大小（例如 ".pyc" 文件），例如在 SQLAlchemy 2.0 的
  "sqlalchemy.orm.session" 中文件大小将减少约 5%。 这项改变将影响各种
  使用了文档字符串的工具，如 "doctest"。

     >>> def spam():
     ...     """
     ...         This is a docstring with
     ...           leading whitespace.
     ...
     ...         It even has multiple paragraphs!
     ...     """
     ...
     >>> spam.__doc__
     '\nThis is a docstring with\n  leading whitespace.\n\nIt even has multiple paragraphs!\n'

  （由 Inada Naoki 在 gh-81283 中贡献。）

* 类作用域内的 标注作用域 现在可以包含 lambda 和推导式。 位于类作用域
  内的推导式不会内联到其父作用域中。

     class C[T]:
         type Alias = lambda: T

  （由 Jelle Zijlstra 在 gh-109118 和 gh-118160 中贡献。）

* future 语句 不再会被 "__future__" 模块的相对导入触发，意味着 "from
  .__future__ import ..." 形式的语句现在只是标准的相对导入，而不会激活
  任何特殊特性。 （由 Jeremiah Gabriel Pascual 在 gh-118216 中贡献。）

* 现在 "global" 声明当其被用于 "else" 代码块中时也将被允许在 "except"
  代码块中使用。 在之前版本中这会错误地引发 "SyntaxError"。 （由 Irit
  Katriel 在 gh-111123 中贡献。）

* 增加了新的环境变量 "PYTHON_FROZEN_MODULES"，它确定冻结模块是否会被导
  入机制所忽略，等价于 "-X frozen_modules" 命令行选项。 （由 Yilei
  Yang 在 gh-111374 中贡献。）

* 通过新的环境变量 "PYTHON_PERF_JIT_SUPPORT" 和命令行选项 "-X
  perf_jit" 添加无需 帧指针 即可工作的 对 perf 性能分析器的支持。 （由
  Pablo Galindo 在 gh-118518 中贡献。）

* 可通过新的 "PYTHON_HISTORY" 环境变量来更改 ".python_history" 文件的
  位置。 （由 Levi Sabah, Zackery Spytz 和 Hugo van Kemenade 在
  gh-73965 中贡献。）

* 类新增了一个 "__static_attributes__" 属性。 这由编译器以类属性名称的
  元组来填充，这些名称是从类体中的任何函数通过 "self.<name>" 来赋值的
  。 （由 Irit Katriel 在 gh-115775 中贡献。）

* 编译器现在会在类上创建一个 "__firstlineno__" 属性，其值为类定义第一
  行的行号。 （由 Serhiy Storchaka 在 gh-118465 中贡献。）

* 现在 "exec()" 和 "eval()" 内置函数接受以关键字形式传入的 *globals*
  和 *locals* 参数。 （由 Raphael Gaschignard 在 gh-105879 中贡献。）

* 现在 "compile()" 内置函数接受一个新的旗标 "ast.PyCF_OPTIMIZED_AST"，
  它类似于 "ast.PyCF_ONLY_AST" 但区别在于返回的 AST 是根据 *optimize*
  参数的值进行优化的。 （由 Irit Katriel 在 gh-108113 中贡献。）

* 在 "property" 对象上增加了 "__name__" 属性。 （由 Eugene Toder 在
  gh-101860 中贡献。）

* 增加了新的异常 "PythonFinalizationError"，它派生自 "RuntimeError"，
  用于当操作在 *最终化* 期间被阻塞时发出信号。 下列可调用对象现在将引
  发 "PythonFinalizationError"，而不是 "RuntimeError":

  * "_thread.start_new_thread()"

  * "os.fork()"

  * "os.forkpty()"

  * "subprocess.Popen"

  （由 Victor Stinner 在 gh-114570 中贡献。）

* 允许 "str.replace()" 的 *count* 参数为关键字参数。 （由 Hugo van
  Kemenade 在 gh-106487 中贡献。）

* 现在许多函数会对将布尔值作为文件描述符参数发出警告。这可以帮助尽早发
  现一些错误。（由 Serhiy Storchaka 在 gh-82626 中贡献。）

* 为 "bz2", "lzma", "tarfile" 和 "zipfile" 等模块中的已压缩和已归档文
  件型对象添加了 "name" 和 "mode" 属性。 （由 Serhiy Storchaka 在
  gh-115961 中贡献。）


新增模块
========

* "dbm.sqlite3": 针对 "dbm" 的 SQLite 后端。 （由 Raymond Hettinger 和
  Erlend E. Aasland 在 gh-100414 中贡献。）


改进的模块
==========


argparse
--------

* 为 "add_argument()" 和 "add_parser()" 方法添加了 *deprecated* 形参，
  以允许弃用命令行选项、位置参数和子命令。 （由 Serhiy Storchaka 在
  gh-83648 中贡献。）


array
-----

* 增加了 "'w'" 类型码 ("Py_UCS4") 表示 Unicode 字符。 它应被用来代替已
  弃用的 "'u'" 类型码。 （由 Inada Naoki 在 gh-80480 中贡献。）

* 通过实现 "clear()" 方法将 "array.array" 注册为 "MutableSequence"。
  （由 Mike Zimin 在 gh-114894 中贡献。）


ast
---

* The constructors of node types in the "ast" module are now stricter
  in the arguments they accept, with more intuitive behavior when
  arguments are omitted.

  如果在构造实例时某个 AST 节点上的可选字段没有被作为参数包括在内，则
  该字段现在将被设为 "None"。 类似地，如果某个列表字段被省略，则该字段
  现在将被设为空列表，而如果某个 "expr_context" 字段被省略，则它将默认
  为 "Load()"。 （之前，在所有情况下，新构造的 AST 节点实例上的相应属
  性都将缺失。）

  在所有其他情况下，当需要的参数被省略时，节点构造器将发出
  "DeprecationWarning"。 这在 Python 3.15 中将会引发异常。 类似地，将
  关键字参数传入一个未映射到 AST 节点上的字段的构造器的做法现在已被弃
  用，并且在 Python 3.15 中将会引发异常。

  这些更改将不会应用于用户自定义的 "ast.AST" 子类，除非该类选择通过设
  置 "AST._field_types" 映射的方式加入新的行为。

  （由 Jelle Zijlstra 在 gh-105858, gh-117486 和 gh-118851 中贡献。）

* 现在 "ast.parse()" 接受一个可选参数 *optimize*，它会被传递给
  "compile()"。 这使得获取已优化的 AST 成为可能。 （由 Irit Katriel 在
  gh-108113 中贡献。）


asyncio
-------

* 现在 "asyncio.as_completed()" 将返回一个即是 *asynchronous iterator*
  又是基本的产生 *可等待对象*  的 *iterator* 的对象。 由异常迭代产生的
  可等待对象包括被传入的原始 Task 或 Future 对象，使得将结果与正在完成
  的任务相关联更为容易。 （由 Justin Arthur 在 gh-77714 中贡献。）

* 现在当服务器被关闭时 "asyncio.loop.create_unix_server()" 会自动移除
  Unix 套接字。 （由 Pierre Ossman 在 gh-111246 中贡献。）

* 现在当附带一个空字节串对象调用时 "DatagramTransport.sendto()" 将发送
  零长度的数据报。 现在当计算缓冲区大小时传输控制流还会将数据报标头纳
  入考量。 （由 Jamie Phan 在 gh-115199 中贡献。）

* 增加了 "Queue.shutdown" 和 "QueueShutDown" 用于管理队列终结。 （由
  Laurie Opperman 和 Yves Duprat 在 gh-104228 中贡献。）

* 增加了 "Server.close_clients()" 和 "Server.abort_clients()" 方法，它
  们会以更强制的方式关闭 asyncio 服务器。 （由 Pierre Ossman 在
  gh-113538 中贡献。）

* 在 "StreamReader.readuntil()" 中接受一个由分隔符组成的元组，当遇到其
  中之一时就会停止。 （由 Bruce Merry 在 gh-81322 中贡献。）

* 改进了 "TaskGroup" 在外部的取消操作与内部的取消操作发生冲突时的行为
  。 例如，当嵌套两个任务分组并且两者同时在某个子任务中遇到异常时，外
  层的任务分组有可能被挂起，因为其内部的取消操作已由内层的任务分组进行
  处理。

  对于任务分组在外部被取消时同时必须引发 "ExceptionGroup" 的情况，现在
  它将调用父任务的 "cancel()" 方法。 这样可以确保 "CancelledError" 会
  在下一次 "await" 时被引发，因此取消操作不会丢失。, so the
  cancellation is not lost.

  这些更改的一个附加好处是现在任务组会保留取消操作计数
  ("cancelling()")。

  为了处理某些边界情况，现在 "uncancel()" 可以在取消操作计数达到零时重
  置未写入文档的 "_must_cancel" 旗标。

  （受到由 Arthur Tacca 在 gh-116720 中报告的问题的启发。）

* 当在一个未激活的 "TaskGroup" 上调用 "TaskGroup.create_task()" 时，给
  定的协程将被关闭 (这将防止引发有关给定的协程从未被等待的
  "RuntimeWarning")。 （由 Arthur Tacca 和 Jason Zhang 在 gh-115957 中
  贡献。）


base64
------

* 增加了 "z85encode()" 和 "z85decode()" 函数用于将 "bytes" 编码为 Z85
  data 和将 Z85 编码的数据解码为 "bytes"。 （由 Matan Perelman 在
  gh-75299 中贡献。）


compileall
----------

* 工作线程和进程的默认数据现在是使用 "os.process_cpu_count()" 而不是
  "os.cpu_count()" 来选择的。 （由 Victor Stinner 在 gh-109649 中贡献
  。）


concurrent.futures
------------------

* 工作线程和进程的默认数据现在是使用 "os.process_cpu_count()" 而不是
  "os.cpu_count()" 来选择的。 （由 Victor Stinner 在 gh-109649 中贡献
  。）


configparser
------------

* 现在 "ConfigParser" 具有对未命名节的支持，这将允许使用最高层级的键值
  对。 此特性可通过新增的 *allow_unnamed_section* 形参来启用。 （由
  Pedro Sousa Lacerda 在 gh-66449 中贡献。）


copy
----

* 新增的 "replace()" 函数和 "replace 协议" 使得创建经修改的对象副本更
  为简单。 这在操作不可变对象时特别有用。 以下类型将支持 "replace()"
  函数并实现了 replace 协议：

  * "collections.namedtuple()"

  * "dataclasses.dataclass"

  * "datetime.datetime", "datetime.date", "datetime.time"

  * "inspect.Signature", "inspect.Parameter"

  * "types.SimpleNamespace"

  * 代码对象

  任何用户自定义类也可以通过定义 "__replace__()" 方法来支持
  "copy.replace()"。 （由 Serhiy Storchaka 在 gh-108751 中贡献。）


dbm
---

* 增加 "dbm.sqlite3"，一个实现了 SQLite 后端的新模块，并将其设为默认的
  "dbm" 后端。 （由 Raymond Hettinger 和 Erlend E. Aasland 在
  gh-100414 中贡献。）

* 允许通过新增的 "gdbm.clear()" 和 "ndbm.clear()" 方法移除数据库中的所
  有条目。 （由 Donghee Na 在 gh-107122 中贡献。）


dis
---

* 将 "dis" 模块的函数的输出修改为显示跳转目标和异常处理器的逻辑标签，
  而不是偏移量。 可以使用新的 "-O" 命令行选项或 *show_offsets* 参数来
  添加偏移量。 （由 Irit Katriel 在 gh-112137 中贡献。）

* "get_instructions()" 不再将缓存条目表示为单独的指令。 作为替代，它会
  将它们作为 "Instruction" 的组成部分返回，放在新的 *cache_info* 字段
  中。 传给 "get_instructions()" 的 *show_caches* 参数已被弃用并且不再
  有任何效果。 （由 Irit Katriel 在 gh-112962 中贡献。）


doctest
-------

* 现在 "doctest" 输出默认是彩色的。 此特性可通过新增的 "PYTHON_COLORS"
  环境变量和传统的 "NO_COLOR" 和 "FORCE_COLOR" 环境变量来控制。 另请参
  阅 控制颜色。 （由 Hugo van Kemenade 在 gh-117225 中贡献。）

* 现在 "DocTestRunner.run()" 方法会统计已跳过测试的数量。 增加了
  "DocTestRunner.skips" 和 "TestResults.skipped" 属性。 （由 Victor
  Stinner 在 gh-108794 中贡献。）


email
-----

* 现在带有嵌入的换行符的标头在输出时会加上引号。 现在 "generator" 会拒
  绝序列化（写入）不正确地折叠或分隔的标头，例如将被解析为多个标头或与
  相邻数据合并的标头等。 如果你需要禁用此安全特性，请设置
  "verify_generated_headers"。 （由 Bas Bloemsaat 和 Petr Viktorin 在
  gh-121650 中贡献。）

* "getaddresses()" and "parseaddr()" now return "('', '')" pairs in
  more situations where invalid email addresses are encountered
  instead of potentially inaccurate values. The two functions have a
  new optional *strict* parameter (default "True"). To get the old
  behavior (accepting malformed input), use "strict=False".
  "getattr(email.utils, 'supports_strict_parsing', False)" can be used
  to check if the *strict* parameter is available. (Contributed by
  Thomas Dwyer and Victor Stinner for gh-102988 to improve the
  CVE-2023-27043 fix.)


fractions
---------

* 现在 "Fraction" 对象支持用于填充、对齐、正负号处理、最小宽度和分组的
  标准 格式说明迷你语言 规则。 （由 Mark Dickinson 在 gh-111320 中贡献
  。）


gc
--

循环垃圾回收器现在是递增式的，这改变了 "get_threshold()" 和
"set_threshold()" 以及 "get_count()" 和 "get_stats()" 的结果的具体含义
。

* 为保持向下兼容，"get_threshold()" 将继续返回一个由三项组成的元组。
  第一项的值是新收集项的阈值，与之前一样；第二项的值决定旧收集项被扫描
  的频度（默认为 10，更高的值意味着旧收集项被扫描的频度更慢）。 第三项
  的值没有意义且始终为零。

* "set_threshold()" 会忽略第二项之后的任何项。

* "get_count()" 和 "get_stats()" 将继续返回相同格式的结果。 唯一的区别
  在于结果不再是指年轻代、中年代和老年代，现在结果是指向年轻代和中年代
  以及老年代的回收空间。

总而言之，尝试操纵循环 GC 的行为的代码可能无法完全如预期一样有效，但也
不太可能产生什么损害。 所有其他代码都会正常执行。


glob
----

* 增加了 "translate()"，这是个用来将具有 shell 风格通配符的路径说明转
  换为正则表达式的函数。 （由 Barney Gale 在 gh-72904 中贡献。）


importlib
---------

* 现在 "importlib.resources" 中的下列函数允许访问资源目录（或树），并
  使用多个位置参数（现在文本读取函数中的 *encoding* 和 *errors* 参数是
  仅限关键字参数）：

  * "is_resource()"

  * "open_binary()"

  * "open_text()"

  * "path()"

  * "read_binary()"

  * "read_text()"

  这些函数将不再被弃用也不会被加入移除计划。 （由 Petr Viktorin 在
  gh-106532 中贡献。）

* "contents()" 仍然被弃用而应改用功能完整的 "Traversable" API。 不过，
  目前还没有移除它的计划。 （由 Petr Viktorin 在 gh-106532 中贡献。）


io
--

* 现在 "IOBase" 最终化器会使用 "sys.unraisablehook" 来将由 "close()"
  方法引发的错误写入日志。 在之前版本中，错误在默认情况下会被静默地忽
  略，而只有在 Python 开发模式 或在使用 Python 调试构建版 时才会被写入
  日志。 （由 Victor Stinner 在 gh-62948 中贡献。）


ipaddress
---------

* 增加了 "IPv4Address.ipv6_mapped" 特征属性，它将返回映射 IPv4 的 IPv6
  地址。 （由 Charles Machalow 在 gh-109466 中贡献。）

* 修正了 "IPv4Address", "IPv6Address", "IPv4Network" 和 "IPv6Network"
  中 "is_global" 和 "is_private" 的行为。 （由 Jakub Stasiak 在
  gh-113171 中贡献。）


itertools
---------

* "batched()" 新增了 *strict* 形参，它会在最后一批次数据小于指定批准大
  小时引发 "ValueError"。 （由 Raymond Hettinger 在 gh-113202 中贡献。
  ）


marshal
-------

* 在模块函数中增加了 *allow_code* 形参。 传入 "allow_code=False" 将防
  止在 Python 各版本间不兼容的代码对象的序列化和反序列化。 （由 Serhiy
  Storchaka 在 gh-113626 中贡献。）


math
----

* 新增函数 "fma()" 可执行合并的乘法-加法运算。 此函数只需一轮操作即可
  计算 "x * y + z"，从而避免了任何中间步骤导致的精度损失。 它包装了
  C99 所提供的 "fma()" 函数，并且遵从针对特殊情况的 IEEE 754
  "fusedMultiplyAdd" 运算规范。 （由 Mark Dickinson 和 Victor Stinner
  在 gh-73468 中贡献。）


mimetypes
---------

* 增加了 "guess_file_type()" 函数用于根据文件系统路径来猜测 MIME 类型
  。 在 "guess_type()" 中使用路径的做法现在已是 *soft deprecated*。 （
  由 Serhiy Storchaka 在 gh-66543 中贡献。）


mmap
----

* 现在 "mmap" 在 Windows 上当被映射的内存由于文件系统错误或访问限制而
  不可访问时将获得保护以避免崩溃。 （由 Jannis Weigend 在 gh-118209 中
  贡献。）

* "mmap" 具有新的 "seekable()" 方法将在需要可定位的文件型对象时被使用
  。 现在 "seek()" 方法将返回一个新的绝对位置。 （由 Donghee Na 和
  Sylvie Liberman 在 gh-111835 中贡献。）

* "mmap" 新增了 UNIX 专属的 *trackfd* 形参用来控制文件描述符的复制；如
  为假值，则由 *fileno* 指定的文件描述符将不会被复制。 （由 Zackery
  Spytz 和 Petr Viktorin 在 gh-78502 中贡献。）


multiprocessing
---------------

* 工作线程和进程的默认数据现在是使用 "os.process_cpu_count()" 而不是
  "os.cpu_count()" 来选择的。 （由 Victor Stinner 在 gh-109649 中贡献
  。）


os
--

* 增加了 "process_cpu_count()" 函数用于获取当前进程的调用方线程可以使
  用的逻辑 CPU 核心数量。 （由 Victor Stinner 在 gh-109649 中贡献。）

* "cpu_count()" 和 "process_cpu_count()" 可通过新的环境变量
  "PYTHON_CPU_COUNT" 或新的命令行选项 "-X cpu_count" 来覆盖。 此选项对
  于需要在不修改应用程序代码或容器本身的情况下限制一个容器系统的 CPU
  资源的用户会很有用处。 （由 Donghee Na 在 gh-109595 中贡献。）

* 通过 "timerfd_create()", "timerfd_settime()",
  "timerfd_settime_ns()", "timerfd_gettime()", "timerfd_gettime_ns()",
  "TFD_NONBLOCK", "TFD_CLOEXEC", "TFD_TIMER_ABSTIME" 和
  "TFD_TIMER_CANCEL_ON_SET" 增加了针对 Linux 的 *计算器文件描述符* 的
  低层级接口。 （由 Masaru Tsuchiyama 在 gh-108277 中贡献。）

* 在 Windows 上现在同时增加了对 "lchmod()" 和 "chmod()" 的
  *follow_symlinks* 参数的支持。 请注意在 Windows 上 "lchmod()" 中的
  *follow_symlinks* 的默认值为 "False"。 （由 Serhiy Storchaka 在
  gh-59616 中贡献。）

* 在 Windows 上现在同时增加了 "fchmod()" 和对 "chmod()" 中的文件描述符
  的支持。 （由 Serhiy Storchaka 在 gh-113191 中贡献。）

* 在 Windows 上，"mkdir()" 和 "makedirs()" 现在支持传入 *mode* 值
  "0o700" 以对新目录应用访问控制。 这会隐式地影响 "tempfile.mkdtemp()"
  并可缓解 CVE-2024-4030。 其他的 *mode* 值仍然会被忽略。 （由 Steve
  Dower 在 gh-118486 中贡献。）

* 现在 "posix_spawn()" 可接受 "None" 作为 *env* 参数，这将让新产生的进
  程使用当前进程的环境。 （由 Jakub Kulik 在 gh-113119 中贡献。）.)

* 在支持 "posix_spawn_file_actions_addclosefrom_np()" 的平台上
  "posix_spawn()" 现在可以在 *file_actions* 形参中使用
  "POSIX_SPAWN_CLOSEFROM" 属性。 （由 Jakub Kulik 在 gh-113117 中贡献
  。）.)


os.path
-------

* 增加了 "isreserved()" 用于检查一个路径在当前系统中是否为保留路径。
  此函数仅在 Windows 上可用。 （由 Barney Gale 在 gh-88569 中贡献。）

* 在 Windows 上，"isabs()" 将不再把以恰好一个斜杠 ("\" 或 "/") 开头的
  路径视为绝对路径。 （由 Barney Gale 和 Jon Foster 在 gh-44626 中贡献
  。）

* 现在即使文件不可访问 "realpath()" 也能够解析 MS-DOS 风格的文件名。
  （由 Moonsik Park 在 gh-82367 中贡献。）


pathlib
-------

* 增加了 "UnsupportedOperation"，它会在一个路径操作不受支持时代替
  "NotImplementedError" 被引发。 （由 Barney Gale 在 gh-89812 中贡献。
  ）

* 新增了一个用于根据 'file' URI ("file:///") 来创建 "Path" 对象的构造
  器 "Path.from_uri()"。 （由 Barney Gale 在 gh-107465 中贡献。）

* 增加了 "PurePath.full_match()" 用于匹配带有 shell 风格通配符的路径，
  包括递归通配符 ""**""。 （由 Barney Gale 在 gh-73435 中贡献。）

* 增加了 "PurePath.parser" 类属性以存储用于低层级路径解析与合并的
  "os.path" 实现。 这可以是 "posixpath" 或 "ntpath"。

* 为 "Path.glob()" 和 "rglob()" 增加了 *recurse_symlinks* 仅限关键字参
  数。 （由 Barney Gale 在 gh-77609 中贡献。）

* 现在当给出以 ""**"" 结束的模式时 "Path.glob()" 和 "rglob()" 将返回文
  件和目录。 在之前版本中，仅会返回目录。 （由 Barney Gale 在 gh-70303
  中贡献。）.)

* 为 "Path.is_file", "Path.is_dir", "Path.owner()" 和 "Path.group()"
  增加了 *follow_symlinks* 仅限关键字参数。 （由 Barney Gale 在
  gh-105793 中，以及 Kamil Turek 在 gh-107962 中贡献。）


pdb
---

* 现在 "breakpoint()" 和 "set_trace()" 会立即进入调试器而不是在被执行
  代码的下一行进入。 这一更改可防止当 "breakpoint()" 位于上下文末尾 时
  调试器在上下文以外被中断。 （由 Tian Gao 在 gh-118579 中贡献。）

* 当设置了 "sys.flags.safe_path" 时 "sys.path[0]" 将不会再被替换为被调
  试脚本的目录。 （由 Tian Gao 和 Christian Walther 在 gh-111762 中贡
  献。）

* 现在支持将 "zipapp" 作为调试目标。 （由 Tian Gao 在 gh-118501 中贡献
  。）

* 添加了在 "pm()" 中进行事后调试期间使用 Pdb 新增的 "exceptions
  [exc_number]" 命令在串连的异常之间移动的能力。 （由 Matthias
  Bussonnier 在 gh-106676 中贡献。）

* 以一条 pdb 命令打头的表达式和语句现在会被正确地标识并执行。 （由
  Tian Gao 在 gh-108464 中贡献。）


queue
-----

* 增加了 "Queue.shutdown" 和 "ShutDown" 用于管理队列的终结。 （由
  Laurie Opperman 和 Yves Duprat 在 gh-104750 中贡献。）


random
------

* 增加了一个 命令行接口。 （由 Hugo van Kemenade 在 gh-118131 中贡献。
  ）


re
--

* 将 "re.error" 重命名为 "PatternError" 以改善准确性。 "re.error" 仍被
  保留用于向下兼容。


shutil
------

* 在 "chown()" 中增加了对 *dir_fd* 和 *follow_symlinks* 关键字参数的支
  持。 （由 Berker Peksag 和 Tahia K 在 gh-62308 中贡献。）


site
----

* 现在 ".pth" 文件将先使用 UTF-8 来解码，如果 UTF-8 解码失败再使用
  *locale encoding*。 （由 Inada Naoki 在 gh-117802 中贡献。）


sqlite3
-------

* 现在当一个 "Connection" 对象未被显式地 "关闭" 时将发出
  "ResourceWarning"。 （由 Erlend E. Aasland 在 gh-105539 中贡献。）

* 为 "Connection.iterdump()" 增加了 *filter* 仅限关键字形参用于过滤要
  转储的数据库对象。 （由 Mariusz Felisiak 在 gh-91602 中贡献。）


ssl
---

* 现在 "create_default_context()" API 将在其默认旗标中包括
  "VERIFY_X509_PARTIAL_CHAIN" 和 "VERIFY_X509_STRICT"。

  备注:

    "VERIFY_X509_STRICT" 可能会拒绝下层 OpenSSL 实现本来会接受的 **RFC
    5280** 以前的证书或格式错误的证书。 虽然不建议禁用此功能，但你可以
    使用以下方式禁用它：

       import ssl

       ctx = ssl.create_default_context()
       ctx.verify_flags &= ~ssl.VERIFY_X509_STRICT

  （由 William Woodruff 在 gh-112389 贡献。）


statistics
----------

* 增加了用于核密度估计的 "kde()"。 这使得根据固定数量的离散样本估计连
  续概率密度函数成为可能。 （由 Raymond Hettinger 在 gh-115863 中贡献
  。）

* 增加了 "kde_random()" 用来从 "kde()" 创建的估计概率密度函数进行取样
  。 （由 Hettinger 在 gh-115863 中贡献。）


subprocess
----------

* 现在 "subprocess" 模块会在更多场合下使用 "posix_spawn()" 函数。

  Notably, when *close_fds* is "True" (the default), "posix_spawn()"
  will be used when the C library provides
  "posix_spawn_file_actions_addclosefrom_np()", which includes recent
  versions of Linux, FreeBSD, and Solaris. On Linux, this should
  perform similarly to the existing Linux "vfork()" based code.

  A private control knob "subprocess._USE_POSIX_SPAWN" can be set to
  "False" if you need to force "subprocess" to never use
  "posix_spawn()". Please report your reason and platform details in
  the issue tracker if you set this so that we can improve our API
  selection logic for everyone. (Contributed by Jakub Kulik in
  gh-113117.)


sys
---

* 增加了 "_is_interned()" 函数用于检测字符串是否被内部化。 此函数不保
  证在所有的 Python 实现中均存在。 （由 Serhiy Storchaka 在 gh-78573
  中贡献。）


tempfile
--------

* 在 Windows 上，"tempfile.mkdtemp()" 所使用的默认模式 "0o700" 由于
  "os.mkdir()" 的更改现在将限制对新目录的访问。 这是对 CVE-2024-4030
  的缓解措施。 （由 Steve Dower 在 gh-118486 中贡献。）


time
----

* 在 Windows 上，"monotonic()" 现在将使用精度为 1 微秒的
  "QueryPerformanceCounter()" 时钟，而不是精度只有 15.6 毫秒的
  "GetTickCount64()" 时钟。 （由 Victor Stinner 在 gh-88494 中贡献。）

* 在 Windows 上，"time()" 现在将使用精度为 1 微秒的
  "GetSystemTimePreciseAsFileTime()" 时钟，代替精度为 15.6 毫秒的
  "GetSystemTimeAsFileTime()" 时钟。 （由 Victor Stinner 在 gh-63207
  中贡献。）


tkinter
-------

* 增加了 "tkinter" 控件方法: "tk_busy_hold()", "tk_busy_configure()",
  "tk_busy_cget()", "tk_busy_forget()", "tk_busy_current()" 和
  "tk_busy_status()"。 （由 Miguel, klappnase 和 Serhiy Storchaka 在
  gh-72684 中贡献。）

* The "tkinter" widget method "wm_attributes()" now accepts the
  attribute name without the minus prefix to get window attributes,
  for example "w.wm_attributes('alpha')" and allows specifying
  attributes and values to set as keyword arguments, for example
  "w.wm_attributes(alpha=0.5)". (Contributed by Serhiy Storchaka in
  gh-43457.)

* "wm_attributes()" can now return attributes as a "dict", by using
  the new optional keyword-only parameter *return_python_dict*.
  (Contributed by Serhiy Storchaka in gh-43457.)

* "Text.count()" can now return a simple "int" when the new optional
  keyword-only parameter *return_ints* is used. Otherwise, the single
  count is returned as a 1-tuple or "None". (Contributed by Serhiy
  Storchaka in gh-97928.)

* 在 "tkinter.ttk.Style" 的 "element_create()" 方法中增加了对 "vsapi"
  元素类型的支持。 （由 Serhiy Storchaka 在 gh-68166 中贡献。）

* 为 Tkinter 的控件增加了 "after_info()" 方法。 （由 Cheryl Sabella 在
  gh-77020 中贡献。）

* 为 "PhotoImage" 新增 "copy_replace()" 方法用于将一个图像的某个区域拷
  贝到另一个图像，可能带有像素缩放、子采样，或两者皆有。 （由 Serhiy
  Storchaka 在 gh-118225 中贡献。）

* 为 "PhotoImage" 的方法 "copy()", "zoom()" 和 "subsample()" 增加了
  *from_coords* 形参。 为 "PhotoImage" 的方法 "copy()" 增加了 *zoom*
  和 *subsample* 形参。 （由 Serhiy Storchaka 在 gh-118225 中贡献。）

* 增加了 "PhotoImage" 方法 "read()" 用于从文件读取图像以及 "data()" 用
  于获取图像数据。 为 "write()" 方法增加了 *background* 和 *grayscale*
  形参。 （由 Serhiy Storchaka 在 gh-118271 中贡献。）.)


回溯
----

* Add the "exc_type_str" attribute to "TracebackException", which
  holds a string display of the *exc_type*. Deprecate the "exc_type"
  attribute, which holds the type object itself. Add parameter
  *save_exc_type* (default "True") to indicate whether "exc_type"
  should be saved. (Contributed by Irit Katriel in gh-112332.)

* Add a new *show_group* keyword-only parameter to
  "TracebackException.format_exception_only()" to (recursively) format
  the nested exceptions of a "BaseExceptionGroup" instance.
  (Contributed by Irit Katriel in gh-105292.)


types
-----

* "SimpleNamespace" can now take a single positional argument to
  initialise the namespace's arguments. This argument must either be a
  mapping or an iterable of key-value pairs. (Contributed by Serhiy
  Storchaka in gh-108191.)


typing
------

* **PEP 705**: Add "ReadOnly", a special typing construct to mark a
  "TypedDict" item as read-only for type checkers.

* **PEP 742**: Add "TypeIs", a typing construct that can be used to
  instruct a type checker how to narrow a type.

* Add "NoDefault", a sentinel object used to represent the defaults of
  some parameters in the "typing" module. (Contributed by Jelle
  Zijlstra in gh-116126.)

* Add "get_protocol_members()" to return the set of members defining a
  "typing.Protocol". (Contributed by Jelle Zijlstra in gh-104873.)

* Add "is_protocol()" to check whether a class is a "Protocol".
  (Contributed by Jelle Zijlstra in gh-104873.)

* "ClassVar" can now be nested in "Final", and vice versa.
  (Contributed by Mehdi Drissi in gh-89547.)


unicodedata
-----------

* Update the Unicode database to version 15.1.0. (Contributed by James
  Gerity in gh-109559.)


venv
----

* Add support for creating source control management (SCM) ignore
  files in a virtual environment's directory. By default, Git is
  supported. This is implemented as opt-in via the API, which can be
  extended to support other SCMs ("EnvBuilder" and "create()"), and
  opt-out via the CLI, using "--without-scm-ignore-files".
  (Contributed by Brett Cannon in gh-108125.)


warnings
--------

* **PEP 702**: The new "warnings.deprecated()" decorator provides a
  way to communicate deprecations to a *static type checker* and to
  warn on usage of deprecated classes and functions. A
  "DeprecationWarning" may also be emitted when a decorated function
  or class is used at runtime. (Contributed by Jelle Zijlstra in
  gh-104003.)


xml
---

* 通过添加五个新方法来允许控制 Expat >=2.6.0 重解析延迟
  (CVE-2023-52425)：

  * "xml.etree.ElementTree.XMLParser.flush()"

  * "xml.etree.ElementTree.XMLPullParser.flush()"

  * "xml.parsers.expat.xmlparser.GetReparseDeferralEnabled()"

  * "xml.parsers.expat.xmlparser.SetReparseDeferralEnabled()"

  * "xml.sax.expatreader.ExpatParser.flush()"

  （由 Sebastian Pipping 在 gh-115623 中贡献。）

* Add the "close()" method for the iterator returned by "iterparse()"
  for explicit cleanup. (Contributed by Serhiy Storchaka in gh-69893.)


zipimport
---------

* Add support for ZIP64 format files. Everybody loves huge data,
  right? (Contributed by Tim Hatch in gh-94146.)


性能优化
========

* The new incremental garbage collector means that maximum pause times
  are reduced by an order of magnitude or more for larger heaps.
  (Contributed by Mark Shannon in gh-108362.)

* Several standard library modules have had their import times
  significantly improved. For example, the import time of the "typing"
  module has been reduced by around a third by removing dependencies
  on "re" and "contextlib". Other modules to enjoy import-time
  speedups include "email.utils", "enum", "functools",
  "importlib.metadata", and "threading". (Contributed by Alex Waygood,
  Shantanu Jain, Adam Turner, Daniel Hollas, and others in gh-109653.)

* "textwrap.indent()" is now around 30% faster than before for large
  input. (Contributed by Inada Naoki in gh-107369.)

* The "subprocess" module now uses the "posix_spawn()" function in
  more situations, including when *close_fds* is "True" (the default)
  on many modern platforms. This should provide a notable performance
  increase when launching processes on FreeBSD and Solaris. See the
  subprocess section above for details. (Contributed by Jakub Kulik in
  gh-113117.)


被移除的模块与 API
==================


PEP 594: Remove "dead batteries" from the standard library
----------------------------------------------------------

**PEP 594** proposed removing 19 modules from the standard library,
colloquially referred to as 'dead batteries' due to their historic,
obsolete, or insecure status. All of the following modules were
deprecated in Python 3.11, and are now removed:

* "aifc"

* "audioop"

* "chunk"

* "cgi" 和 "cgitb"

  * "cgi.FieldStorage" can typically be replaced with
    "urllib.parse.parse_qsl()" for "GET" and "HEAD" requests, and the
    "email.message" module or the multipart library for "POST" and
    "PUT" requests.

  * "cgi.parse()" can be replaced by calling "urllib.parse.parse_qs()"
    directly on the desired query string, unless the input is
    "multipart/form-data", which should be replaced as described below
    for "cgi.parse_multipart()".

  * "cgi.parse_header()" can be replaced with the functionality in the
    "email" package, which implements the same MIME RFCs. For example,
    with "email.message.EmailMessage":

       from email.message import EmailMessage

       msg = EmailMessage()
       msg['content-type'] = 'application/json; charset="utf8"'
       main, params = msg.get_content_type(), msg['content-type'].params

  * "cgi.parse_multipart()" can be replaced with the functionality in
    the "email" package, which implements the same MIME RFCs, or with
    the multipart library. For example, the
    "email.message.EmailMessage" and "email.message.Message" classes.

* "crypt" and the private "_crypt" extension. The "hashlib" module may
  be an appropriate replacement when simply hashing a value is
  required. Otherwise, various third-party libraries on PyPI are
  available:

  * bcrypt: 用于软件和服务器的现代密码哈希算法。

  * passlib: 支持超过 over 30 种方案的综合密码哈希算法框架。

  * argon2-cffi: 安全的 Argon2 密码哈希算法。

  * legacycrypt: 针对 POSIX 加密库调用和相关功能的 "ctypes" 包装器。

  * crypt_r: "crypt" 模块的分叉，针对 *crypt_r(3)* 库调用和相关功能和
    包装器。

* "imghdr": The filetype, puremagic, or python-magic libraries should
  be used as replacements. For example, the "puremagic.what()"
  function can be used to replace the "imghdr.what()" function for all
  file formats that were supported by "imghdr".

* "mailcap": 改用 "mimetypes" 模块。

* "msilib"

* "nis"

* "nntplib": 改用 PyPI 上的 nntplib 库。

* "ossaudiodev": 对于音频回放，改用 PyPI 上的 pygame 库。

* "pipes": 改用 "subprocess" 模块。

* "sndhdr": 应当使用 filetype, puremagic 或 python-magic 库作为替代。

* "spwd": Use the python-pam library from PyPI instead.

* "sunau"

* "telnetlib"，改用 PyPI 上的 telnetlib3 或 Exscript 库。

* "uu": 改用 the "base64" 模块，作为一款现代化的替代。

* "xdrlib"

（由 Victor Stinner 和 Zachary Ware 在 gh-104773 和 gh-104780 中贡献。
）


2to3
----

* Remove the **2to3** program and the "lib2to3" module, previously
  deprecated in Python 3.11. (Contributed by Victor Stinner in
  gh-104780.)


builtins
--------

* Remove support for chained "classmethod" descriptors (introduced in
  gh-63272). These can no longer be used to wrap other descriptors,
  such as "property". The core design of this feature was flawed and
  led to several problems. To "pass-through" a "classmethod", consider
  using the "__wrapped__" attribute that was added in Python 3.10.
  (Contributed by Raymond Hettinger in gh-89519.)

* Raise a "RuntimeError" when calling "frame.clear()" on a suspended
  frame (as has always been the case for an executing frame).
  (Contributed by Irit Katriel in gh-79932.)


configparser
------------

* Remove the undocumented "LegacyInterpolation" class, deprecated in
  the docstring since Python 3.2, and at runtime since Python 3.11.
  (Contributed by Hugo van Kemenade in gh-104886.)


importlib.metadata
------------------

* Remove deprecated subscript ("__getitem__()") access for EntryPoint
  objects. (Contributed by Jason R. Coombs in gh-113175.)


locale
------

* Remove the "locale.resetlocale()" function, deprecated in Python
  3.11. Use "locale.setlocale(locale.LC_ALL, "")" instead.
  (Contributed by Victor Stinner in gh-104783.)


opcode
------

* Move "opcode.ENABLE_SPECIALIZATION" to
  "_opcode.ENABLE_SPECIALIZATION". This field was added in 3.12, it
  was never documented, and is not intended for external use.
  (Contributed by Irit Katriel in gh-105481.)

* Remove "opcode.is_pseudo()", "opcode.MIN_PSEUDO_OPCODE", and
  "opcode.MAX_PSEUDO_OPCODE", which were added in Python 3.12, but
  were neither documented nor exposed through "dis", and were not
  intended to be used externally. (Contributed by Irit Katriel in
  gh-105481.)


pathlib
-------

* Remove the ability to use "Path" objects as context managers. This
  functionality was deprecated and has had no effect since Python 3.9.
  (Contributed by Barney Gale in gh-83863.)


re
--

* Remove the undocumented, deprecated, and broken "re.template()"
  function and "re.TEMPLATE" / "re.T" flag. (Contributed by Serhiy
  Storchaka and Nikita Sobolev in gh-105687.)


tkinter.tix
-----------

* Remove the "tkinter.tix" module, deprecated in Python 3.6. The
  third-party Tix library which the module wrapped is unmaintained.
  (Contributed by Zachary Ware in gh-75552.)


turtle
------

* Remove the "RawTurtle.settiltangle()" method, deprecated in the
  documentation since Python 3.1 and at runtime since Python 3.11.
  (Contributed by Hugo van Kemenade in gh-104876.)


typing
------

* Remove the "typing.io" and "typing.re" namespaces, deprecated since
  Python 3.8. The items in those namespaces can be imported directly
  from the "typing" module. (Contributed by Sebastian Rittau in
  gh-92871.)

* Remove the keyword-argument method of creating "TypedDict" types,
  deprecated in Python 3.11. (Contributed by Tomas Roun in gh-104786.)


unittest
--------

* 移除了下列 "unittest" 函数，它们在 Python 3.11 中已被弃用：

  * "unittest.findTestCases()"

  * "unittest.makeSuite()"

  * "unittest.getTestCaseNames()"

  请改用 "TestLoader" 方法:

  * "loadTestsFromModule()"

  * "loadTestsFromTestCase()"

  * "getTestCaseNames()"

  （由 Hugo van Kemenade 在 gh-104835 中贡献。）

* Remove the untested and undocumented "TestProgram.usageExit()"
  method, deprecated in Python 3.11. (Contributed by Hugo van Kemenade
  in gh-104992.)


urllib
------

* Remove the *cafile*, *capath*, and *cadefault* parameters of the
  "urllib.request.urlopen()" function, deprecated in Python 3.6. Use
  the *context* parameter instead with an "SSLContext" instance. The
  "ssl.SSLContext.load_cert_chain()" function can be used to load
  specific certificates, or let "ssl.create_default_context()" select
  the operating system's trusted certificate authority (CA)
  certificates. (Contributed by Victor Stinner in gh-105382.)


webbrowser
----------

* Remove the untested and undocumented "MacOSX" class, deprecated in
  Python 3.11. Use the "MacOSXOSAScript" class (introduced in Python
  3.2) instead. (Contributed by Hugo van Kemenade in gh-104804.)

* Remove the deprecated "MacOSXOSAScript._name" attribute. Use the
  "MacOSXOSAScript.name" attribute instead. (Contributed by Nikita
  Sobolev in gh-105546.)


新的弃用
========

* User-defined functions:

  * Deprecate assignment to a function's "__code__" attribute, where
    the new code object's type does not match the function's type. The
    different types are: plain function, generator, async generator,
    and coroutine. (Contributed by Irit Katriel in gh-81137.)

* "array":

  * Deprecate the "'u'" format code ("wchar_t") at runtime. This
    format code has been deprecated in documentation since Python 3.3,
    and will be removed in Python 3.16. Use the "'w'" format code
    ("Py_UCS4") for Unicode characters instead. (Contributed by Hugo
    van Kemenade in gh-80480.)

* "ctypes":

  * Deprecate the undocumented "SetPointerType()" function, to be
    removed in Python 3.15. (Contributed by Victor Stinner in
    gh-105733.)

  * *Soft-deprecate* the "ARRAY()" function in favour of "type *
    length" multiplication. (Contributed by Victor Stinner in
    gh-105733.)

* "decimal":

  * Deprecate the non-standard and undocumented "Decimal" format
    specifier "'N'", which is only supported in the "decimal" module's
    C implementation. (Contributed by Serhiy Storchaka in gh-89902.)

* "dis":

  * Deprecate the "HAVE_ARGUMENT" separator. Check membership in
    "hasarg" instead. (Contributed by Irit Katriel in gh-109319.)

* "getopt" and "optparse":

  * Both modules are now *soft deprecated*, with "argparse" preferred
    for new projects. This is a new soft-deprecation for the "getopt"
    module, whereas the "optparse" module was already *de facto* soft
    deprecated. (Contributed by Victor Stinner in gh-106535.)

* "gettext":

  * Deprecate non-integer numbers as arguments to functions and
    methods that consider plural forms in the "gettext" module, even
    if no translation was found. (Contributed by Serhiy Storchaka in
    gh-88434.)

* "glob":

  * Deprecate the undocumented "glob0()" and "glob1()" functions. Use
    "glob()" and pass a *path-like object* specifying the root
    directory to the *root_dir* parameter instead. (Contributed by
    Barney Gale in gh-117337.)

* "http.server":

  * Deprecate "CGIHTTPRequestHandler", to be removed in Python 3.15.
    Process-based CGI HTTP servers have been out of favor for a very
    long time. This code was outdated, unmaintained, and rarely used.
    It has a high potential for both security and functionality bugs.
    (Contributed by Gregory P. Smith in gh-109096.)

  * Deprecate the "--cgi" flag to the **python -m http.server**
    command-line interface, to be removed in Python 3.15. (Contributed
    by Gregory P. Smith in gh-109096.)

* "mimetypes":

  * *Soft-deprecate* file path arguments to "guess_type()", use
    "guess_file_type()" instead. (Contributed by Serhiy Storchaka in
    gh-66543.)

* "re":

  * Deprecate passing the optional *maxsplit*, *count*, or *flags*
    arguments as positional arguments to the module-level "split()",
    "sub()", and "subn()" functions. These parameters will become
    keyword-only in a future version of Python. (Contributed by Serhiy
    Storchaka in gh-56166.)

* "pathlib":

  * Deprecate "PurePath.is_reserved()", to be removed in Python 3.15.
    Use "os.path.isreserved()" to detect reserved paths on Windows.
    (Contributed by Barney Gale in gh-88569.)

* "platform":

  * Deprecate "java_ver()", to be removed in Python 3.15. This
    function is only useful for Jython support, has a confusing API,
    and is largely untested. (Contributed by Nikita Sobolev in
    gh-116349.)

* "pydoc":

  * Deprecate the undocumented "ispackage()" function. (Contributed by
    Zackery Spytz in gh-64020.)

* "sqlite3":

  * Deprecate passing more than one positional argument to the
    "connect()" function and the "Connection" constructor. The
    remaining parameters will become keyword-only in Python 3.15.
    (Contributed by Erlend E. Aasland in gh-107948.)

  * Deprecate passing name, number of arguments, and the callable as
    keyword arguments for "Connection.create_function()" and
    "Connection.create_aggregate()" These parameters will become
    positional-only in Python 3.15. (Contributed by Erlend E. Aasland
    in gh-108278.)

  * Deprecate passing the callback callable by keyword for the
    "set_authorizer()", "set_progress_handler()", and
    "set_trace_callback()" "Connection" methods. The callback
    callables will become positional-only in Python 3.15. (Contributed
    by Erlend E. Aasland in gh-108278.)

* "sys":

  * Deprecate the "_enablelegacywindowsfsencoding()" function, to be
    removed in Python 3.16. Use the "PYTHONLEGACYWINDOWSFSENCODING"
    environment variable instead. (Contributed by Inada Naoki in
    gh-73427.)

* "tarfile":

  * Deprecate the undocumented and unused "TarFile.tarfile" attribute,
    to be removed in Python 3.16. (Contributed in gh-115256.)

* "traceback":

  * Deprecate the "TracebackException.exc_type" attribute. Use
    "TracebackException.exc_type_str" instead. (Contributed by Irit
    Katriel in gh-112332.)

* "typing":

  * Deprecate the undocumented keyword argument syntax for creating
    "NamedTuple" classes (e.g. "Point = NamedTuple("Point", x=int,
    y=int)"), to be removed in Python 3.15. Use the class-based syntax
    or the functional syntax instead. (Contributed by Alex Waygood in
    gh-105566.)

  * Deprecate omitting the *fields* parameter when creating a
    "NamedTuple" or "typing.TypedDict" class, and deprecate passing
    "None" to the *fields* parameter of both types. Python 3.15 will
    require a valid sequence for the *fields* parameter. To create a
    NamedTuple class with zero fields, use "class NT(NamedTuple):
    pass" or "NT = NamedTuple("NT", ())". To create a TypedDict class
    with zero fields, use "class TD(TypedDict): pass" or "TD =
    TypedDict("TD", {})". (Contributed by Alex Waygood in gh-105566
    and gh-105570.)

  * Deprecate the "typing.no_type_check_decorator()" decorator
    function, to be removed in in Python 3.15. After eight years in
    the "typing" module, it has yet to be supported by any major type
    checker. (Contributed by Alex Waygood in gh-106309.)

  * Deprecate "typing.AnyStr". In Python 3.16, it will be removed from
    "typing.__all__", and a "DeprecationWarning" will be emitted at
    runtime when it is imported or accessed. It will be removed
    entirely in Python 3.18. Use the new type parameter syntax
    instead. (Contributed by Michael The in gh-107116.)

* "wave":

  * Deprecate the "getmark()", "setmark()", and "getmarkers()" methods
    of the "Wave_read" and "Wave_write" classes, to be removed in
    Python 3.15. (Contributed by Victor Stinner in gh-105096.)


计划在 Python 3.14 中移除
-------------------------

* "argparse": "argparse.BooleanOptionalAction" 的 *type*, *choices* 和
  *metavar* 形参已被弃用并将在 3.14 中移除。 （由 Nikita Sobolev 在
  gh-92248 中贡献。）

* "ast": 以下特性自 Python 3.8 起已在文档中声明弃用，现在当运行时如果
  它们被访问或使用时将发出 "DeprecationWarning"，并将在 Python 3.14 中
  移除：

  * "ast.Num"

  * "ast.Str"

  * "ast.Bytes"

  * "ast.NameConstant"

  * "ast.Ellipsis"

  请改用 "ast.Constant"。 （由 Serhiy Storchaka 在 gh-90953 中贡献。）

* "asyncio":

  * The child watcher classes "asyncio.MultiLoopChildWatcher",
    "asyncio.FastChildWatcher", "asyncio.AbstractChildWatcher" and
    "asyncio.SafeChildWatcher" are deprecated and will be removed in
    Python 3.14. (Contributed by Kumar Aditya in gh-94597.)

  * "asyncio.set_child_watcher()", "asyncio.get_child_watcher()",
    "asyncio.AbstractEventLoopPolicy.set_child_watcher()" and
    "asyncio.AbstractEventLoopPolicy.get_child_watcher()" are
    deprecated and will be removed in Python 3.14. (Contributed by
    Kumar Aditya in gh-94597.)

  * 现在默认事件循环策略的 "get_event_loop()" 方法在当前事件循环未设置
    并决定创建一个时将发出 "DeprecationWarning"。 （由 Serhiy
    Storchaka 和 Guido van Rossum 在 gh-100160 中贡献。）

* "collections.abc": Deprecated "collections.abc.ByteString". Prefer
  "Sequence" or "Buffer". For use in typing, prefer a union, like
  "bytes | bytearray", or "collections.abc.Buffer". (Contributed by
  Shantanu Jain in gh-91896.)

* "email": 已弃用 "email.utils.localtime()" 中的 *isdst* 形参。 （由
  Alan Williams 在 gh-72346 中贡献。）

* "importlib.abc" 中已弃用的类：

  * "importlib.abc.ResourceReader"

  * "importlib.abc.Traversable"

  * "importlib.abc.TraversableResources"

  使用 "importlib.resources.abc" 类代替:

  * "importlib.resources.abc.Traversable"

  * "importlib.resources.abc.TraversableResources"

  （由 Jason R. Coombs 和 Hugo van Kemenade 在 gh-93963 中贡献。）

* "itertools" 具有对 copy, deepcopy 和 pickle 等操作的未写入文档的、低
  效的、历史上充满问题的且不稳定的支持。 这将在 3.14 中移除以显著减少
  代码量和维护负担。 （由 Raymond Hettinger 在 gh-101588 中贡献。）

* "multiprocessing": 默认的启动方法在目前默认使用 "'fork'" 的 Linux,
  BSD 和其他非 macOS POSIX 平台上将改为更安全的方法 (gh-84559)。 为此
  添加运行时警告将带来糟糕的体验因为大部分代码并不会关心这个问题。 当
  你的代码 *需要* "'fork'" 时请使用 "get_context()" 或
  "set_start_method()" API 来显式地指明。 参见 上下文和启动方法。

* "pathlib": "is_relative_to()" 和 "relative_to()": 传入额外参数的做法
  已被弃用。

* "pkgutil": 现在 "find_loader()" 和 "get_loader()" 将引发
  "DeprecationWarning"；请改用 "importlib.util.find_spec()"。 （由
  Nikita Sobolev 在 gh-97850 中贡献。）

* "pty":

  * "master_open()": 使用 "pty.openpty()"。

  * "slave_open()": 使用 "pty.openpty()"。

* "sqlite3":

  * "version" and "version_info".

  * 如果使用了 命名占位符 且 *parameters* 是一个序列而不是 "dict" 则选
    择 "execute()" 和 "executemany()"。

  * date 和 datetime 适配器，date 和 timestamp 转换器：请参阅
    "sqlite3" 文档了解推荐的替代方案。

* "types.CodeType": 访问 "co_lnotab" 的做法自 3.10 起已在 **PEP 626**
  中被弃用并曾计划在 3.12 中移除，但实际上在 3.12 中仅设置了
  "DeprecationWarning"。 可能会在 3.14 中移除。 （由 Nikita Sobolev 在
  gh-101866 中贡献。）

* "typing": "typing.ByteString", deprecated since Python 3.9, now
  causes a "DeprecationWarning" to be emitted when it is used.

* "urllib": "urllib.parse.Quoter" 已被弃用：它不应被作为公有 API。 （
  由 Gregory P. Smith 在 gh-88168 中贡献。）


Python 3.15 中的待移除功能
--------------------------

* "ctypes":

  * The undocumented "ctypes.SetPointerType()" function has been
    deprecated since Python 3.13.

* "http.server":

  * The obsolete and rarely used "CGIHTTPRequestHandler" has been
    deprecated since Python 3.13. No direct replacement exists.
    *Anything* is better than CGI to interface a web server with a
    request handler.

  * The "--cgi" flag to the **python -m http.server** command-line
    interface has been deprecated since Python 3.13.

* "importlib": "__package__" 和 "__cached__" 将不再被设置或是被导入系
  统纳入考量 (gh-97879)。

* "locale":

  * The "getdefaultlocale()" function has been deprecated since Python
    3.11. Its removal was originally planned for Python 3.13
    (gh-90817), but has been postponed to Python 3.15. Use
    "getlocale()", "setlocale()", and "getencoding()" instead.
    (Contributed by Hugo van Kemenade in gh-111187.)

* "pathlib":

  * "PurePath.is_reserved()" has been deprecated since Python 3.13.
    Use "os.path.isreserved()" to detect reserved paths on Windows.

* "platform":

  * "java_ver()" has been deprecated since Python 3.13. This function
    is only useful for Jython support, has a confusing API, and is
    largely untested.

* "threading":

  * "RLock()" will take no arguments in Python 3.15. Passing any
    arguments has been deprecated since Python 3.14, as the  Python
    version does not permit any arguments, but the C version allows
    any number of positional or keyword arguments, ignoring every
    argument.

* "typing":

  * The undocumented keyword argument syntax for creating "NamedTuple"
    classes (e.g. "Point = NamedTuple("Point", x=int, y=int)") has
    been deprecated since Python 3.13. Use the class-based syntax or
    the functional syntax instead.

  * The "typing.no_type_check_decorator()" decorator function has been
    deprecated since Python 3.13. After eight years in the "typing"
    module, it has yet to be supported by any major type checker.

* "wave":

  * The "getmark()", "setmark()", and "getmarkers()" methods of the
    "Wave_read" and "Wave_write" classes have been deprecated since
    Python 3.13.


计划在 Python 3.16 中移除
-------------------------

* "builtins":

  * Bitwise inversion on boolean types, "~True" or "~False" has been
    deprecated since Python 3.12, as it produces surprising and
    unintuitive results ("-2" and "-1"). Use "not x" instead for the
    logical negation of a Boolean. In the rare case that you need the
    bitwise inversion of the underlying integer, convert to "int"
    explicitly ("~int(x)").

* "array":

  * The "'u'" format code ("wchar_t") has been deprecated in
    documentation since Python 3.3 and at runtime since Python 3.13.
    Use the "'w'" format code ("Py_UCS4") for Unicode characters
    instead.

* "shutil":

  * The "ExecError" exception has been deprecated since Python 3.14.
    It has not been used by any function in "shutil" since Python 3.4,
    and is now an alias of "RuntimeError".

* "symtable":

  * The "Class.get_methods" method has been deprecated since Python
    3.14.

* "sys":

  * The "_enablelegacywindowsfsencoding()" function has been
    deprecated since Python 3.13. Use the
    "PYTHONLEGACYWINDOWSFSENCODING" environment variable instead.

* "tarfile":

  * The undocumented and unused "TarFile.tarfile" attribute has been
    deprecated since Python 3.13.


计划在未来版本中移除
--------------------

以下API将会被移除，尽管具体时间还未确定。

* "argparse": 嵌套参数分组和嵌套互斥分组的做法已被弃用。

* "array" 的 "'u'" 格式代码 (gh-57281)

* "builtins":

  * "bool(NotImplemented)"。

  * 生成器: "throw(type, exc, tb)" 和 "athrow(type, exc, tb)" 签名已被
    弃用：请改用 "throw(exc)" 和 "athrow(exc)"，即单参数签名。

  * 目前 Python 接受数字类字面值后面紧跟关键字的写法，例如 "0in x",
    "1or x", "0if 1else 2"。 它允许像 "[0x1for x in y]" 这样令人困惑且
    有歧义的表达式 (它可以被解读为 "[0x1 for x in y]" 或者 "[0x1f or x
    in y]")。 如果数字类字面值后面紧跟关键字 "and", "else", "for",
    "if", "in", "is" 和 "or" 中的一个将会引发语法警告。 在未来的版本中
    它将改为语法错误。 (gh-87999)

  * 对 "__index__()" 和 "__int__()" 方法返回非 int 类型的支持：将要求
    这些方法必须返回 "int" 的子类的实例。

  * 对 "__float__()" 方法返回 "float" 的子类的支持：将要求这些方法必须
    返回 "float" 的实例。

  * 对 "__complex__()" 方法返回 "complex" 的子类的支持：将要求这些方法
    必须返回 "complex" 的实例。

  * 将 "int()" 委托给 "__trunc__()" 方法。

  * 传入一个复数作为 "complex()" 构造器中的 *real* 或 *imag* 参数的做
    法现在已被弃用；它应当仅作为单个位置参数被传入。 （由 Serhiy
    Storchaka 在 gh-109218 中贡献。）.)

* "calendar": "calendar.January" 和 "calendar.February" 常量已被弃用并
  由 "calendar.JANUARY" 和 "calendar.FEBRUARY" 替代。 （由 Prince
  Roshan 在 gh-103636 中贡献。）

* "codeobject.co_lnotab": 改用 "codeobject.co_lines()" 方法。

* "datetime":

  * "utcnow()": 使用 "datetime.datetime.now(tz=datetime.UTC)"。

  * "utcfromtimestamp()": 使用
    "datetime.datetime.fromtimestamp(timestamp, tz=datetime.UTC)"。

* "gettext": 复数值必须是一个整数。

* "importlib":

  * "load_module()" 方法：改用 "exec_module()"。

  * "cache_from_source()" *debug_override* 形参已被弃用：改用
    *optimization* 形能耐。

* "importlib.metadata":

  * "EntryPoints" 元组接口。

  * 返回值中隐式的 "None"。

* "logging": "warn()" 方法自 Python 3.3 起已被弃用，请改用 "warning()"
  。

* "mailbox": 对 StringIO 输入和文本模式的使用已被弃用，改用 BytesIO 和
  二进制模式。

* "os": 在多线程的进程中调用 "os.register_at_fork()"。

* "pydoc.ErrorDuringImport": 使用元组值作为 *exc_info* 形参的做法已被
  弃用，应使用异常实例。

* "re": 现在对于正则表达式中的数字分组引用和分组名称将应用更严格的规则
  。 现在只接受 ASCII 数字序列作为数字引用。 字节串模式和替换字符串中
  的分组名称现在只能包含 ASCII 字母和数字以及下划线。 （由 Serhiy
  Storchaka 在 gh-91760 中贡献。）

* "sre_compile", "sre_constants" 和 "sre_parse" 模块。

* "shutil": "rmtree()" 的 *onerror* 形参在 Python 3.12 中已被弃用；请
  改用 *onexc* 形参。

* "ssl" 选项和协议：

  * "ssl.SSLContext" 不带 protocol 参数的做法已被弃用。

  * "ssl.SSLContext": "set_npn_protocols()" 和
    "selected_npn_protocol()" 已被弃用：请改用 ALPN.

  * "ssl.OP_NO_SSL*" 选项

  * "ssl.OP_NO_TLS*" 选项

  * "ssl.PROTOCOL_SSLv3"

  * "ssl.PROTOCOL_TLS"

  * "ssl.PROTOCOL_TLSv1"

  * "ssl.PROTOCOL_TLSv1_1"

  * "ssl.PROTOCOL_TLSv1_2"

  * "ssl.TLSVersion.SSLv3"

  * "ssl.TLSVersion.TLSv1"

  * "ssl.TLSVersion.TLSv1_1"

* "sysconfig.is_python_build()" *check_home* 形参已被弃用并会被忽略。

* "threading" 的方法：

  * "threading.Condition.notifyAll()": 使用 "notify_all()"。

  * "threading.Event.isSet()": 使用 "is_set()"。

  * "threading.Thread.isDaemon()", "threading.Thread.setDaemon()": 使
    用 "threading.Thread.daemon" 属性。

  * "threading.Thread.getName()", "threading.Thread.setName()": 使用
    "threading.Thread.name" 属性。

  * "threading.currentThread()": 使用 "threading.current_thread()"。

  * "threading.activeCount()": 使用 "threading.active_count()"。

* "typing.Text" (gh-92332)。

* "unittest.IsolatedAsyncioTestCase": 从测试用例返回不为 "None" 的值的
  做法已被弃用。

* "urllib.parse" 函数已被弃用：改用 "urlparse()"

  * "splitattr()"

  * "splithost()"

  * "splitnport()"

  * "splitpasswd()"

  * "splitport()"

  * "splitquery()"

  * "splittag()"

  * "splittype()"

  * "splituser()"

  * "splitvalue()"

  * "to_bytes()"

* "urllib.request": 发起请求的 "URLopener" 和 "FancyURLopener" 方式已
  被弃用。 改用更新 "urlopen()" 函数和方法。

* "wsgiref": "SimpleHandler.stdout.write()" 不应执行部分写入。

* "xml.etree.ElementTree": 对 "Element" 的真值测试已被弃用。 在未来的
  发布版中它将始终返回 "True"。 建议改用显式的 "len(elem)" 或 "elem is
  not None" 测试。

* "zipimport.zipimporter.load_module()" 已被弃用：请改用
  "exec_module()"。


CPython 字节码的变化
====================

* The oparg of "YIELD_VALUE" is now "1" if the yield is part of a
  yield-from or await, and "0" otherwise. The oparg of "RESUME" was
  changed to add a bit indicating if the except-depth is 1, which is
  needed to optimize closing of generators. (Contributed by Irit
  Katriel in gh-111354.)


C API 的变化
============


新的特性
--------

* Add the PyMonitoring C API for generating **PEP 669** monitoring
  events:

  * "PyMonitoringState"

  * "PyMonitoring_FirePyStartEvent()"

  * "PyMonitoring_FirePyResumeEvent()"

  * "PyMonitoring_FirePyReturnEvent()"

  * "PyMonitoring_FirePyYieldEvent()"

  * "PyMonitoring_FireCallEvent()"

  * "PyMonitoring_FireLineEvent()"

  * "PyMonitoring_FireJumpEvent()"

  * "PyMonitoring_FireBranchEvent()"

  * "PyMonitoring_FireCReturnEvent()"

  * "PyMonitoring_FirePyThrowEvent()"

  * "PyMonitoring_FireRaiseEvent()"

  * "PyMonitoring_FireCRaiseEvent()"

  * "PyMonitoring_FireReraiseEvent()"

  * "PyMonitoring_FireExceptionHandledEvent()"

  * "PyMonitoring_FirePyUnwindEvent()"

  * "PyMonitoring_FireStopIterationEvent()"

  * "PyMonitoring_EnterScope()"

  * "PyMonitoring_ExitScope()"

  (Contributed by Irit Katriel in gh-111997).

* Add "PyMutex", a lightweight mutex that occupies a single byte, and
  the new "PyMutex_Lock()" and "PyMutex_Unlock()" functions.
  "PyMutex_Lock()" will release the *GIL* (if currently held) if the
  operation needs to block. (Contributed by Sam Gross in gh-108724.)

* Add the PyTime C API to provide access to system clocks:

  * "PyTime_t".

  * "PyTime_MIN" and "PyTime_MAX".

  * "PyTime_AsSecondsDouble()"。

  * "PyTime_Monotonic()"。

  * "PyTime_MonotonicRaw()"。

  * "PyTime_PerfCounter()"。

  * "PyTime_PerfCounterRaw()"。

  * "PyTime_Time()"。

  * "PyTime_TimeRaw()"。

  （由 Victor Stinner 和 Petr Viktorin 在 gh-110850 中贡献。）

* Add the "PyDict_ContainsString()" function with the same behavior as
  "PyDict_Contains()", but *key* is specified as a const char* UTF-8
  encoded bytes string, rather than a PyObject*. (Contributed by
  Victor Stinner in gh-108314.)

* Add the "PyDict_GetItemRef()" and "PyDict_GetItemStringRef()"
  functions, which behave similarly to "PyDict_GetItemWithError()",
  but return a  *strong reference* instead of a *borrowed reference*.
  Moreover, these functions return "-1" on error, removing the need to
  check "PyErr_Occurred()". (Contributed by Victor Stinner in
  gh-106004.)

* Add the "PyDict_SetDefaultRef()" function, which behaves similarly
  to "PyDict_SetDefault()", but returns a *strong reference* instead
  of a *borrowed reference*. This function returns "-1" on error, "0"
  on insertion, and "1" if the key was already present in the
  dictionary. (Contributed by Sam Gross in gh-112066.)

* Add the "PyDict_Pop()" and "PyDict_PopString()" functions to remove
  a key from a dictionary and optionally return the removed value.
  This is similar to "dict.pop()", though there is no default value,
  and "KeyError" is not raised for missing keys. (Contributed by
  Stefan Behnel and Victor Stinner in gh-111262.)

* Add the "PyMapping_GetOptionalItem()" and
  "PyMapping_GetOptionalItemString()" functions as alternatives to
  "PyObject_GetItem()" and "PyMapping_GetItemString()" respectively.
  The new functions do not raise "KeyError" if the requested key is
  missing from the mapping. These variants are more convenient and
  faster if a missing key should not be treated as a failure.
  (Contributed by Serhiy Storchaka in gh-106307.)

* Add the "PyObject_GetOptionalAttr()" and
  "PyObject_GetOptionalAttrString()" functions as alternatives to
  "PyObject_GetAttr()" and "PyObject_GetAttrString()" respectively.
  The new functions do not raise "AttributeError" if the requested
  attribute is not found on the object. These variants are more
  convenient and faster if the missing attribute should not be treated
  as a failure. (Contributed by Serhiy Storchaka in gh-106521.)

* Add the "PyErr_FormatUnraisable()" function as an extension to
  "PyErr_WriteUnraisable()" that allows customizing the warning
  message. (Contributed by Serhiy Storchaka in gh-108082.)

* Add new functions that return a *strong reference* instead of a
  *borrowed reference* for frame locals, globals, and builtins, as
  part of PEP 667:

  * "PyEval_GetFrameBuiltins()" replaces "PyEval_GetBuiltins()"

  * "PyEval_GetFrameGlobals()" replaces "PyEval_GetGlobals()"

  * "PyEval_GetFrameLocals()" replaces "PyEval_GetLocals()"

  (Contributed by Mark Shannon and Tian Gao in gh-74929.)

* Add the "Py_GetConstant()" and "Py_GetConstantBorrowed()" functions
  to get *strong* or *borrowed* references to constants. For example,
  "Py_GetConstant(Py_CONSTANT_ZERO)" returns a strong reference to the
  constant zero. (Contributed by Victor  Stinner in gh-115754.)

* Add the "PyImport_AddModuleRef()" function as a replacement for
  "PyImport_AddModule()" that returns a *strong reference* instead of
  a *borrowed reference*. (Contributed by Victor Stinner in
  gh-105922.)

* Add the "Py_IsFinalizing()" function to check whether the main
  Python interpreter is *shutting down*. (Contributed by Victor
  Stinner in gh-108014.)

* Add the "PyList_GetItemRef()" function as a replacement for
  "PyList_GetItem()" that returns a *strong reference* instead of a
  *borrowed reference*. (Contributed by Sam Gross in gh-114329.)

* Add the "PyList_Extend()" and "PyList_Clear()" functions, mirroring
  the Python "list.extend()" and "list.clear()" methods. (Contributed
  by Victor Stinner in gh-111138.)

* Add the "PyLong_AsInt()" function. It behaves similarly to
  "PyLong_AsLong()", but stores the result in a C int instead of a C
  long. (Contributed by Victor Stinner in gh-108014.)

* Add the "PyLong_AsNativeBytes()", "PyLong_FromNativeBytes()", and
  "PyLong_FromUnsignedNativeBytes()" functions to simplify converting
  between native integer types and Python "int" objects. (Contributed
  by Steve Dower in gh-111140.)

* Add "PyModule_Add()" function, which is similar to
  "PyModule_AddObjectRef()" and "PyModule_AddObject()", but always
  steals a reference to the value. (Contributed by Serhiy Storchaka in
  gh-86493.)

* Add the "PyObject_GenericHash()" function that implements the
  default hashing function of a Python object. (Contributed by Serhiy
  Storchaka in gh-113024.)

* Add the "Py_HashPointer()" function to hash a raw pointer.
  (Contributed by Victor Stinner in gh-111545.)

* Add the "PyObject_VisitManagedDict()" and
  "PyObject_ClearManagedDict()" functions. which must be called by the
  traverse and clear functions of a type using the
  "Py_TPFLAGS_MANAGED_DICT" flag. The pythoncapi-compat project can be
  used to use these functions with Python 3.11 and 3.12. (Contributed
  by Victor Stinner in gh-107073.)

* Add the "PyRefTracer_SetTracer()" and "PyRefTracer_GetTracer()"
  functions, which enable tracking object creation and destruction in
  the same way that the "tracemalloc" module does. (Contributed by
  Pablo Galindo in gh-93502.)

* Add the "PySys_AuditTuple()" function as an alternative to
  "PySys_Audit()" that takes event arguments as a Python "tuple"
  object. (Contributed by Victor Stinner in gh-85283.)

* Add the "PyThreadState_GetUnchecked()" function as an alternative to
  "PyThreadState_Get()" that doesn't kill the process with a fatal
  error if it is "NULL". The caller is responsible for checking if the
  result is "NULL". (Contributed by Victor Stinner in gh-108867.)

* Add the "PyType_GetFullyQualifiedName()" function to get the type's
  fully qualified name. The module name is prepended if
  "type.__module__" is a string and is not equal to either
  "'builtins'" or "'__main__'". (Contributed by Victor Stinner in
  gh-111696.)

* Add the "PyType_GetModuleName()" function to get the type's module
  name. This is equivalent to getting the "type.__module__" attribute.
  (Contributed by Eric Snow and Victor Stinner in gh-111696.)

* Add the "PyUnicode_EqualToUTF8AndSize()" and
  "PyUnicode_EqualToUTF8()" functions to compare a Unicode object with
  a const char* UTF-8 encoded string and "1" if they are equal or "0"
  otherwise. These functions do not raise exceptions. (Contributed by
  Serhiy Storchaka in gh-110289.)

* Add the "PyWeakref_GetRef()" function as an alternative to
  "PyWeakref_GetObject()" that returns a *strong reference* or "NULL"
  if the referent is no longer live. (Contributed by Victor Stinner in
  gh-105927.)

* 增加了静默地忽略错误的函数的已修正变体形式：

  * "PyObject_HasAttrWithError()" 替代 "PyObject_HasAttr()"。

  * "PyObject_HasAttrStringWithError()" 替代
    "PyObject_HasAttrString()"。

  * "PyMapping_HasKeyWithError()" 替代 "PyMapping_HasKey()"。

  * "PyMapping_HasKeyStringWithError()" 替代
    "PyMapping_HasKeyString()"。

  The new functions return "-1" for errors and the standard "1" for
  true and "0" for false.

  （由 Serhiy Storchaka 在 gh-108511 中贡献。）


Changed C APIs
--------------

* The *keywords* parameter of "PyArg_ParseTupleAndKeywords()" and
  "PyArg_VaParseTupleAndKeywords()" now has type char *const* in C and
  const char *const* in C++, instead of char**. In C++, this makes
  these functions compatible with arguments of type const char
  *const*, const char**, or char *const* without an explicit type
  cast. In C, the functions only support arguments of type char
  *const*. This can be overridden with the "PY_CXX_CONST" macro.
  (Contributed by Serhiy Storchaka in gh-65210.)

* "PyArg_ParseTupleAndKeywords()" now supports non-ASCII keyword
  parameter names. (Contributed by Serhiy Storchaka in gh-110815.)

* The "PyCode_GetFirstFree()" function is now unstable API and is now
  named "PyUnstable_Code_GetFirstFree()". (Contributed by Bogdan
  Romanyuk in gh-115781.)

* The "PyDict_GetItem()", "PyDict_GetItemString()",
  "PyMapping_HasKey()", "PyMapping_HasKeyString()",
  "PyObject_HasAttr()", "PyObject_HasAttrString()", and
  "PySys_GetObject()" functions, each of which clears all errors which
  occurred when calling them now reports these errors using
  "sys.unraisablehook()". You may replace them with other functions as
  recommended in the documentation. (Contributed by Serhiy Storchaka
  in gh-106672.)

* Add support for the "%T", "%#T", "%N" and "%#N" formats to
  "PyUnicode_FromFormat()":

  * "%T": Get the fully qualified name of an object type

  * "%#T": As above, but use a colon as the separator

  * "%N": Get the fully qualified name of a type

  * "%#N": As above, but use a colon as the separator

  See **PEP 737** for more information. (Contributed by Victor Stinner
  in gh-111696.)

* You no longer have to define the "PY_SSIZE_T_CLEAN" macro before
  including "Python.h" when using "#" formats in format codes. APIs
  accepting the format codes always use "Py_ssize_t" for "#" formats.
  (Contributed by Inada Naoki in gh-104922.)

* 如果 Python 是使用 调试模式 或 "附带断言" 构建的，
  "PyTuple_SET_ITEM()" 和 "PyList_SET_ITEM()" 现在将通过一个断言来检查
  index 参数。 （由 Victor Stinner 在 gh-106168 中贡献。）


Limited C API Changes
---------------------

* The following functions are now included in the Limited C API:

  * "PyMem_RawMalloc()"

  * "PyMem_RawCalloc()"

  * "PyMem_RawRealloc()"

  * "PyMem_RawFree()"

  * "PySys_Audit()"

  * "PySys_AuditTuple()"

  * "PyType_GetModuleByDef()"

  (Contributed by Victor Stinner in gh-85283, gh-85283, and
  gh-116936.)

* Python built with "--with-trace-refs" (tracing references) now
  supports the Limited API. (Contributed by Victor Stinner in
  gh-108634.)


Removed C APIs
--------------

* Remove several functions, macros, variables, etc with names prefixed
  by "_Py" or "_PY" (which are considered private). If your project is
  affected  by one of these removals and you believe that the removed
  API should remain available, please open a new issue to request a
  public C API and add "cc: @vstinner" to the issue to notify Victor
  Stinner. (Contributed by Victor Stinner in gh-106320.)

* Remove old buffer protocols deprecated in Python 3.0. Use 缓冲协议
  instead.

  * "PyObject_CheckReadBuffer()": Use "PyObject_CheckBuffer()" to test
    whether the object supports the buffer protocol. Note that
    "PyObject_CheckBuffer()" doesn't guarantee that
    "PyObject_GetBuffer()" will succeed. To test if the object is
    actually readable, see the next example of "PyObject_GetBuffer()".

  * "PyObject_AsCharBuffer()", "PyObject_AsReadBuffer()": Use
    "PyObject_GetBuffer()" and "PyBuffer_Release()" instead:

       Py_buffer view;
       if (PyObject_GetBuffer(obj, &view, PyBUF_SIMPLE) < 0) {
           return NULL;
       }
       // Use `view.buf` and `view.len` to read from the buffer.
       // You may need to cast buf as `(const char*)view.buf`.
       PyBuffer_Release(&view);

  * "PyObject_AsWriteBuffer()": Use "PyObject_GetBuffer()" and
    "PyBuffer_Release()" instead:

       Py_buffer view;
       if (PyObject_GetBuffer(obj, &view, PyBUF_WRITABLE) < 0) {
           return NULL;
       }
       // Use `view.buf` and `view.len` to write to the buffer.
       PyBuffer_Release(&view);

  (Contributed by Inada Naoki in gh-85275.)

* Remove various functions deprecated in Python 3.9:

  * "PyEval_CallObject()", "PyEval_CallObjectWithKeywords()": Use
    "PyObject_CallNoArgs()" or "PyObject_Call()" instead.

    警告:

      In "PyObject_Call()", positional arguments must be a "tuple" and
      must not be "NULL", and keyword arguments must be a "dict" or
      "NULL", whereas the removed functions checked argument types and
      accepted "NULL" positional and keyword arguments. To replace
      "PyEval_CallObjectWithKeywords(func, NULL, kwargs)" with
      "PyObject_Call()", pass an empty tuple as positional arguments
      using "PyTuple_New(0)".

  * "PyEval_CallFunction()": Use "PyObject_CallFunction()" instead.

  * "PyEval_CallMethod()": Use "PyObject_CallMethod()" instead.

  * "PyCFunction_Call()": Use "PyObject_Call()" instead.

  (Contributed by Victor Stinner in gh-105107.)

* Remove the following old functions to configure the Python
  initialization, deprecated in Python 3.11:

  * "PySys_AddWarnOptionUnicode()": Use "PyConfig.warnoptions"
    instead.

  * "PySys_AddWarnOption()": Use "PyConfig.warnoptions" instead.

  * "PySys_AddXOption()": Use "PyConfig.xoptions" instead.

  * "PySys_HasWarnOptions()": Use "PyConfig.xoptions" instead.

  * "PySys_SetPath()": Set "PyConfig.module_search_paths" instead.

  * "Py_SetPath()": Set "PyConfig.module_search_paths" instead.

  * "Py_SetStandardStreamEncoding()": Set "PyConfig.stdio_encoding"
    instead, and set also maybe "PyConfig.legacy_windows_stdio" (on
    Windows).

  * "_Py_SetProgramFullPath()": Set "PyConfig.executable" instead.

  Use the new "PyConfig" API of the Python Initialization
  Configuration instead (**PEP 587**), added to Python 3.8.
  (Contributed by Victor Stinner in gh-105145.)

* Remove "PyEval_AcquireLock()" and "PyEval_ReleaseLock()" functions,
  deprecated in Python 3.2. They didn't update the current thread
  state. They can be replaced with:

  * "PyEval_SaveThread()" and "PyEval_RestoreThread()";

  * low-level "PyEval_AcquireThread()" and "PyEval_RestoreThread()";

  * or "PyGILState_Ensure()" and "PyGILState_Release()".

  (Contributed by Victor Stinner in gh-105182.)

* Remove the "PyEval_ThreadsInitialized()" function, deprecated in
  Python 3.9. Since Python 3.7, "Py_Initialize()" always creates the
  GIL: calling "PyEval_InitThreads()" does nothing and
  "PyEval_ThreadsInitialized()" always returns non-zero. (Contributed
  by Victor Stinner in gh-105182.)

* Remove the "_PyInterpreterState_Get()" alias to
  "PyInterpreterState_Get()" which was kept for backward compatibility
  with Python 3.8. The pythoncapi-compat project can be used to get
  "PyInterpreterState_Get()" on Python 3.8 and older. (Contributed by
  Victor Stinner in gh-106320.)

* Remove the private "_PyObject_FastCall()" function: use
  "PyObject_Vectorcall()" which is available since Python 3.8 (**PEP
  590**). (Contributed by Victor Stinner in gh-106023.)

* Remove the "cpython/pytime.h" header file, which only contained
  private functions. (Contributed by Victor Stinner in gh-106316.)

* Remove the undocumented "PY_TIMEOUT_MAX" constant from the limited C
  API. (Contributed by Victor Stinner in gh-110014.)

* Remove the old trashcan macros "Py_TRASHCAN_SAFE_BEGIN" and
  "Py_TRASHCAN_SAFE_END". Replace both with the new macros
  "Py_TRASHCAN_BEGIN" and "Py_TRASHCAN_END". (Contributed by Irit
  Katriel in gh-105111.)


已弃用的 C API
--------------

* 已弃用旧的 Python 初始化函数：

  * "PySys_ResetWarnOptions()": Clear "sys.warnoptions" and
    "warnings.filters" instead.

  * "Py_GetExecPrefix()": Get "sys.exec_prefix" instead.

  * "Py_GetPath()": Get "sys.path" instead.

  * "Py_GetPrefix()": Get "sys.prefix" instead.

  * "Py_GetProgramFullPath()": Get "sys.executable" instead.

  * "Py_GetProgramName()": Get "sys.executable" instead.

  * "Py_GetPythonHome()": Get "PyConfig.home" or the "PYTHONHOME"
    environment variable instead.

  (Contributed by Victor Stinner in gh-105145.)

* *Soft deprecate* the "PyEval_GetBuiltins()", "PyEval_GetGlobals()",
  and "PyEval_GetLocals()" functions, which return a *borrowed
  reference*. (Soft deprecated as part of **PEP 667**.)

* Deprecate the "PyImport_ImportModuleNoBlock()" function, which is
  just an alias to "PyImport_ImportModule()" since Python 3.3.
  (Contributed by Victor Stinner in gh-105396.)

* *Soft deprecate* the "PyModule_AddObject()" function. It should be
  replaced with "PyModule_Add()" or "PyModule_AddObjectRef()".
  (Contributed by Serhiy Storchaka in gh-86493.)

* Deprecate the old "Py_UNICODE" and "PY_UNICODE_TYPE" types and the
  "Py_UNICODE_WIDE" define. Use the "wchar_t" type directly instead.
  Since Python 3.3, "Py_UNICODE" and "PY_UNICODE_TYPE" are just
  aliases to "wchar_t". (Contributed by Victor Stinner in gh-105156.)

* Deprecate the "PyWeakref_GetObject()" and "PyWeakref_GET_OBJECT()"
  functions, which return a *borrowed reference*. Replace them with
  the new "PyWeakref_GetRef()" function, which returns a *strong
  reference*. The pythoncapi-compat project can be used to get
  "PyWeakref_GetRef()" on Python 3.12 and older. (Contributed by
  Victor Stinner in gh-105927.)


计划在 Python 3.14 中移除
~~~~~~~~~~~~~~~~~~~~~~~~~

* "PyDictObject" 中的 "ma_version_tag" 字段用于扩展模块 ( **PEP 699**
  ; gh-101193 )。

* 创建 "immutable types"  的可变基础 ( gh-95388 )。

* 用于配置 Python 的初始化的函数，在 Python 3.11 中已弃用：

  * "PySys_SetArgvEx()": Set "PyConfig.argv" instead.

  * "PySys_SetArgv()": Set "PyConfig.argv" instead.

  * "Py_SetProgramName()": Set "PyConfig.program_name" instead.

  * "Py_SetPythonHome()": Set "PyConfig.home" instead.

  "Py_InitializeFromConfig()" API 应与 "PyConfig" 一起使用。

* 全局配置变量：

  * "Py_DebugFlag": Use "PyConfig.parser_debug" instead.

  * "Py_VerboseFlag": Use "PyConfig.verbose" instead.

  * "Py_QuietFlag": Use "PyConfig.quiet" instead.

  * "Py_InteractiveFlag": Use "PyConfig.interactive" instead.

  * "Py_InspectFlag": Use "PyConfig.inspect" instead.

  * "Py_OptimizeFlag": Use "PyConfig.optimization_level" instead.

  * "Py_NoSiteFlag": Use "PyConfig.site_import" instead.

  * "Py_BytesWarningFlag": Use "PyConfig.bytes_warning" instead.

  * "Py_FrozenFlag": Use "PyConfig.pathconfig_warnings" instead.

  * "Py_IgnoreEnvironmentFlag": Use "PyConfig.use_environment"
    instead.

  * "Py_DontWriteBytecodeFlag": Use "PyConfig.write_bytecode" instead.

  * "Py_NoUserSiteDirectory": Use "PyConfig.user_site_directory"
    instead.

  * "Py_UnbufferedStdioFlag": Use "PyConfig.buffered_stdio" instead.

  * "Py_HashRandomizationFlag": Use "PyConfig.use_hash_seed" and
    "PyConfig.hash_seed" instead.

  * "Py_IsolatedFlag": Use "PyConfig.isolated" instead.

  * "Py_LegacyWindowsFSEncodingFlag": Use
    "PyPreConfig.legacy_windows_fs_encoding" instead.

  * "Py_LegacyWindowsStdioFlag": Use "PyConfig.legacy_windows_stdio"
    instead.

  * "Py_FileSystemDefaultEncoding": Use "PyConfig.filesystem_encoding"
    instead.

  * "Py_HasFileSystemDefaultEncoding": Use
    "PyConfig.filesystem_encoding" instead.

  * "Py_FileSystemDefaultEncodeErrors": Use
    "PyConfig.filesystem_errors" instead.

  * "Py_UTF8Mode": Use "PyPreConfig.utf8_mode" instead. (see
    "Py_PreInitialize()")

  "Py_InitializeFromConfig()" API 应与 "PyConfig" 一起使用。


Python 3.15 中的待移除功能
~~~~~~~~~~~~~~~~~~~~~~~~~~

* 捆绑的 "libmpdecimal" 副本。

* The "PyImport_ImportModuleNoBlock()": Use "PyImport_ImportModule()"
  instead.

* "PyWeakref_GetObject()" and "PyWeakref_GET_OBJECT()": Use
  "PyWeakref_GetRef()" instead.

* "Py_UNICODE" type and the "Py_UNICODE_WIDE" macro: Use "wchar_t"
  instead.

* Python 初始化函数

  * "PySys_ResetWarnOptions()": Clear "sys.warnoptions" and
    "warnings.filters" instead.

  * "Py_GetExecPrefix()": Get "sys.exec_prefix" instead.

  * "Py_GetPath()": Get "sys.path" instead.

  * "Py_GetPrefix()": Get "sys.prefix" instead.

  * "Py_GetProgramFullPath()": Get "sys.executable" instead.

  * "Py_GetProgramName()": Get "sys.executable" instead.

  * "Py_GetPythonHome()": Get "PyConfig.home" or the "PYTHONHOME"
    environment variable instead.


计划在未来版本中移除
~~~~~~~~~~~~~~~~~~~~

以下 API 已被弃用，将被移除，但目前尚未确定移除日期。

* "Py_TPFLAGS_HAVE_FINALIZE": Unneeded since Python 3.8.

* "PyErr_Fetch()": Use "PyErr_GetRaisedException()" instead.

* "PyErr_NormalizeException()": Use "PyErr_GetRaisedException()"
  instead.

* "PyErr_Restore()": Use "PyErr_SetRaisedException()" instead.

* "PyModule_GetFilename()": Use "PyModule_GetFilenameObject()"
  instead.

* "PyOS_AfterFork()": Use "PyOS_AfterFork_Child()" instead.

* "PySlice_GetIndicesEx()": Use "PySlice_Unpack()" and
  "PySlice_AdjustIndices()" instead.

* "PyUnicode_AsDecodedObject()": Use "PyCodec_Decode()" instead.

* "PyUnicode_AsDecodedUnicode()": Use "PyCodec_Decode()" instead.

* "PyUnicode_AsEncodedObject()": Use "PyCodec_Encode()" instead.

* "PyUnicode_AsEncodedUnicode()": Use "PyCodec_Encode()" instead.

* "PyUnicode_READY()": Unneeded since Python 3.12

* "PyErr_Display()": Use "PyErr_DisplayException()" instead.

* "_PyErr_ChainExceptions()": Use "_PyErr_ChainExceptions1()" instead.

* "PyBytesObject.ob_shash" 成员：改为调用 "PyObject_Hash()"。

* "PyDictObject.ma_version_tag" 成员。

* 线程本地存储 (TLS) API：

  * "PyThread_create_key()": Use "PyThread_tss_alloc()" instead.

  * "PyThread_delete_key()": Use "PyThread_tss_free()" instead.

  * "PyThread_set_key_value()": Use "PyThread_tss_set()" instead.

  * "PyThread_get_key_value()": Use "PyThread_tss_get()" instead.

  * "PyThread_delete_key_value()": Use "PyThread_tss_delete()"
    instead.

  * "PyThread_ReInitTLS()": Unneeded since Python 3.7.


构建变化
========

* "arm64-apple-ios" and "arm64-apple-ios-simulator" are both now **PEP
  11** tier 3 platforms. (PEP 730 written and implementation
  contributed by Russell Keith-Magee in gh-114099.)

* "aarch64-linux-android" and "x86_64-linux-android" are both now
  **PEP 11** tier 3 platforms. (PEP 738 written and implementation
  contributed by Malcolm Smith in gh-116622.)

* 现在 "wasm32-wasi" 是 **PEP 11** 第 2 层级的平台。 （由 Brett Cannon
  在 gh-115192 中贡献。）

* "wasm32-emscripten" 不再是 **PEP 11** 的受支持平台。 （由 Brett
  Cannon 在 gh-115192 中贡献。）

* 现在构建 CPython 需要带有 C11 atomic 库支持的编译器、GCC 内置 atomic
  函数或 MSVC 互锁内生函数。

* 现在需要有 autoconf 2.71 和 aclocal 1.16.4 才能重新生成 "configure"
  脚本。 （由 Christian Heimes 在 gh-89886 中贡献。）

* 需要 SQLite 3.15.2 或更新的版本才能构建 "sqlite3" 扩展模块。 （由
  Erlend Aasland 在 gh-105875 中贡献。）

* CPython now bundles the mimalloc library by default. It is licensed
  under the MIT license; see mimalloc license. The bundled mimalloc
  has custom changes, see gh-113141 for details. (Contributed by Dino
  Viehland in gh-109914.)

* 现在 "configure" 选项 "--with-system-libmpdec" 默认为 "yes"。 捆绑的
  "libmpdecimal" 副本将在 Python 3.15 中被移除。

* 使用 "configure" "--with-trace-refs" (跟踪引用) 构建的 Python 现在与
  Python 发布构建版和 调试构建版 是 ABI 兼容的。 （由 Victor Stinner
  在 gh-108634 中贡献。）

* On POSIX systems, the pkg-config (".pc") filenames now include the
  ABI flags.  For example, the free-threaded build generates
  "python-3.13t.pc" and the debug build generates "python-3.13d.pc".

* 现在 "errno", "fcntl", "grp", "md5", "pwd", "resource", "termios",
  "winsound", "_ctypes_test", "_multiprocessing.posixshmem",
  "_scproxy", "_stat", "_statistics", "_testconsole",
  "_testimportmultiple" 和 "_uuid" C 扩展是使用 受限 C API 构建的。 （
  由 Victor Stinner 在 gh-85283 中贡献。）


Porting to Python 3.13
======================

本节列出了先前描述的更改以及可能需要更改代码的其他错误修正.


Python API 的变化
-----------------

* PEP 667 introduces several changes to the semantics of "locals()"
  and "f_locals":

  * Calling "locals()" in an *optimized scope* now produces an
    independent snapshot on each call, and hence no longer implicitly
    updates previously returned references. Obtaining the legacy
    CPython behavior now requires explicit calls to update the
    initially returned dictionary with the results of subsequent calls
    to "locals()". Code execution functions that implicitly target
    "locals()" (such as "exec" and "eval") must be passed an explicit
    namespace to access their results in an optimized scope. (Changed
    as part of **PEP 667**.)

  * Calling "locals()" from a comprehension at module or class scope
    (including via "exec" or "eval") once more behaves as if the
    comprehension were running as an independent nested function (i.e.
    the local variables from the containing scope are not included).
    In Python 3.12, this had changed to include the local variables
    from the containing scope when implementing **PEP 709**. (Changed
    as part of **PEP 667**.)

  * Accessing "FrameType.f_locals" in an *optimized scope* now returns
    a write-through proxy rather than a snapshot that gets updated at
    ill-specified times. If a snapshot is desired, it must be created
    explicitly with "dict" or the proxy's ".copy()" method. (Changed
    as part of **PEP 667**.)

* "functools.partial" now emits a "FutureWarning" when used as a
  method. The behavior will change in future Python versions. Wrap it
  in "staticmethod()" if you want to preserve the old behavior.
  (Contributed by Serhiy Storchaka in gh-121027.)

* The garbage collector is now incremental, which means that the
  behavior of "gc.collect()" changes slightly:

  * "gc.collect(1)": Performs an increment of garbage collection,
    rather than collecting generation 1.

  * 其他对 "gc.collect()" 的调用没有变化。

* An "OSError" is now raised by "getpass.getuser()" for any failure to
  retrieve a username, instead of "ImportError" on non-Unix platforms
  or "KeyError" on Unix platforms where the password database is
  empty.

* The value of the "mode" attribute of "gzip.GzipFile" is now a string
  ("'rb'" or "'wb'") instead of an integer ("1" or "2"). The value of
  the "mode" attribute of the readable file-like object returned by
  "zipfile.ZipFile.open()" is now "'rb'" instead of "'r'".
  (Contributed by Serhiy Storchaka in gh-115961.)

* "mailbox.Maildir" now ignores files with a leading dot (".").
  (Contributed by Zackery Spytz in gh-65559.)

* "pathlib.Path.glob()" and "rglob()" now return both files and
  directories if a pattern that ends with ""**"" is given, rather than
  directories only. Add a trailing slash to keep the previous behavior
  and only match directories.

* The "threading" module now expects the "_thread" module to have an
  "_is_main_interpreter()" function. This function takes no arguments
  and returns "True" if the current interpreter is the main
  interpreter.

  Any library or application that provides a custom "_thread" module
  must provide "_is_main_interpreter()", just like the module's other
  "private" attributes. (gh-112826.)


C API 的变化
------------

* "Python.h" no longer includes the "<ieeefp.h>" standard header. It
  was included for the "finite()" function which is now provided by
  the "<math.h>" header. It should now be included explicitly if
  needed. Remove also the "HAVE_IEEEFP_H" macro. (Contributed by
  Victor Stinner in gh-108765.)

* "Python.h" no longer includes these standard header files:
  "<time.h>", "<sys/select.h>" and "<sys/time.h>". If needed, they
  should now be included explicitly. For example, "<time.h>" provides
  the "clock()" and "gmtime()" functions, "<sys/select.h>" provides
  the "select()" function, and "<sys/time.h>" provides the
  "futimes()", "gettimeofday()" and "setitimer()" functions.
  (Contributed by Victor Stinner in gh-108765.)

* On Windows, "Python.h" no longer includes the "<stddef.h>" standard
  header file. If needed, it should now be included explicitly. For
  example, it provides "offsetof()" function, and "size_t" and
  "ptrdiff_t" types. Including "<stddef.h>" explicitly was already
  needed by all other platforms, the "HAVE_STDDEF_H" macro is only
  defined on Windows. (Contributed by Victor Stinner in gh-108765.)

* If the "Py_LIMITED_API" macro is defined, "Py_BUILD_CORE",
  "Py_BUILD_CORE_BUILTIN" and "Py_BUILD_CORE_MODULE" macros are now
  undefined by "<Python.h>". (Contributed by Victor Stinner in
  gh-85283.)

* The old trashcan macros "Py_TRASHCAN_SAFE_BEGIN" and
  "Py_TRASHCAN_SAFE_END" were removed. They should be replaced by the
  new macros "Py_TRASHCAN_BEGIN" and "Py_TRASHCAN_END".

  A "tp_dealloc" function that has the old macros, such as:

     static void
     mytype_dealloc(mytype *p)
     {
         PyObject_GC_UnTrack(p);
         Py_TRASHCAN_SAFE_BEGIN(p);
         ...
         Py_TRASHCAN_SAFE_END
     }

  应当按照以下方式迁移到新版宏:

     static void
     mytype_dealloc(mytype *p)
     {
         PyObject_GC_UnTrack(p);
         Py_TRASHCAN_BEGIN(p, mytype_dealloc)
         ...
         Py_TRASHCAN_END
     }

  Note that "Py_TRASHCAN_BEGIN" has a second argument which should be
  the deallocation function it is in. The new macros were added in
  Python 3.8 and the old macros were deprecated in Python 3.11.
  (Contributed by Irit Katriel in gh-105111.)

* PEP 667 introduces several changes to frame-related functions:

  * The effects of mutating the dictionary returned from
    "PyEval_GetLocals()" in an *optimized scope* have changed. New
    dict entries added this way will now *only* be visible to
    subsequent "PyEval_GetLocals()" calls in that frame, as
    "PyFrame_GetLocals()", "locals()", and "FrameType.f_locals" no
    longer access the same underlying cached dictionary. Changes made
    to entries for actual variable names and names added via the
    write-through proxy interfaces will be overwritten on subsequent
    calls to "PyEval_GetLocals()" in that frame. The recommended code
    update depends on how the function was being used, so refer to the
    deprecation notice on the function for details.

  * Calling "PyFrame_GetLocals()" in an *optimized scope* now returns
    a write-through proxy rather than a snapshot that gets updated at
    ill-specified times. If a snapshot is desired, it must be created
    explicitly (e.g. with "PyDict_Copy()"), or by calling the new
    "PyEval_GetFrameLocals()" API.

  * "PyFrame_FastToLocals()" and "PyFrame_FastToLocalsWithError()" no
    longer have any effect. Calling these functions has been redundant
    since Python 3.11, when "PyFrame_GetLocals()" was first
    introduced.

  * "PyFrame_LocalsToFast()" no longer has any effect. Calling this
    function is redundant now that "PyFrame_GetLocals()" returns a
    write-through proxy for *optimized scopes*.


回归测试的变化
==============

* 现在使用 "configure" "--with-pydebug" 编译的 Python 将支持 "-X
  presite=package.module" 命令行选项。 如果被使用，它指明一个模块应当
  在解释器生命周期开始时，即 "site.py" 被执行之前被导入。 （由 Łukasz
  Langa 在 gh-110769 中贡献。）
