Python 3.13 有什么新变化¶
- 编者:
Thomas Wouters
本文介绍了 Python 3.13 相比 3.12 的新增特性。
完整的详情可参阅 更新日志。
也參考
PEP 719 -- Python 3.13 发布计划
備註
预发布版用户应当了解到此文档目前处于草稿状态。 它将随着 Python 3.13 的发步进程不断更新,因此即使已经阅读过较早的版本也仍然值得再次查看。
摘要 -- 发布重点¶
Python 3.13 beta 是 Python 编译语言下一正式版本的预发布版本,包含多项针对语言、实现和标准库的改变。 针对实现的最大改变包括新的交互式解释器,以及对于去除全局解释器锁 (PEP 703) 和启用即时编译器 (PEP 744) 的实验性支持。 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改进。
解释器的改进:
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
andNO_COLOR
环境变量来禁用。增加了 PEP 744: 基本的 JIT 编译器。 目前默认是禁用的(但以后可能启用)。 能够小幅度提升性能 -- 我们预计在接下来的几个发布版中不断改进它。
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。
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: 支持使用新的
warnings.deprecated()
装饰器在类型系统中对弃用进行标记。PEP 742: 增加了
typing.TypeIs
,提供更直观的类型细化行为。PEP 705: 增加了
typing.ReadOnly
,用于将typing.TypedDict
的项标记为对类型检查器只读。
自由线程:
PEP 703: 当使用
--disable-gil
编译时 CPython 3.13 将支持在运行时禁用 global interpreter lock。 请参阅 自由线程 CPython 了解详情。
平台支持:
移除的模块:
PEP 594: 剩余的 19 个“死电池”已从标准库中移除:
aifc
,audioop
,cgi
,cgitb
,chunk
,crypt
,imghdr
,mailcap
,msilib
,nis
,nntplib
,ossaudiodev
,pipes
,sndhdr
,spwd
,sunau
,telnetlib
,uu
和xdrlib
。此外还移除了
tkinter.tix
和lib2to3
模块,以及2to3
程序。
发布计划的变化:
PEP 602 ("Annual Release Cycle for Python") 已更新:
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¶
在类 Unix 系统如 Linux 或 macOS 上以及在 Windows 上,Python 现在将使用新的 interactive shell。 当用户从交互式终端启动 REPL 时这个交互式 shell 现在将支持以下新特性:
带颜色的提示符。
多行编辑并保留历史记录。
使用 F1 浏览交互式帮助并带有单独的命令历史。
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)。
可以输入 REPL 专属的命令如 help, exit 和 quit 而无需使用在命令名后添加圆括号的调用形式。
如果不想要新的交互式 shell,可以通过 PYTHON_BASIC_REPL
环境变量禁用它。
在类 Unix 平台上新的 shell 需要 curses
。
交互模式的内容详见 互動模式。
(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¶
在显示异常回溯时,解释器现在会默认为错误消息着色。这个特性可以用新引入的
PYTHON_COLORS
以及经典的NO_COLOR
和FORCE_COLOR
环境变量控制。参见 控制颜色。(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/random.py", line 1, in <module> import random; print(random.randint(5)) ^^^^^^^^^^^^^ File "/home/random.py", line 1, in <module> import random; print(random.randint(5)) ^^^^^^^^^^^^^^ AttributeError: module 'random' has no attribute 'randint' (consider renaming '/home/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,如果一个脚本和它尝试导入的某个第三方模块重名,并且因此产生错误,同样会显示一条更有用的错误信息:
$ python numpy.py Traceback (most recent call last): File "/home/numpy.py", line 1, in <module> import numpy as np; np.array([1,2,3]) ^^^^^^^^^^^^^^^^^^ File "/home/numpy.py", line 1, in <module> import numpy as np; np.array([1,2,3]) ^^^^^^^^ AttributeError: module 'numpy' has no attribute 'array' (consider renaming '/home/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)。
往函数传入错误关键字参数时,现在错误信息可能会提示正确的关键字参数。(由 Pablo Galindo Salgado 和 Shantanu Jain 在 gh-107944 中贡献。)
>>> "better error messages!".split(max_split=1) Traceback (most recent call last): File "<stdin>", line 1, in <module> "better error messages!".split(max_split=1) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^ TypeError: split() got an unexpected keyword argument 'max_split'. Did you mean 'maxsplit'?
类现在有一个由编译器填充的新属性
__static_attributes__
,它是一个元组,包含以self.X
形式从类体中定义的任何函数访问的属性。(由 Irit Katriel 在 gh-115775 中贡献)。
针对 locals()
的已定义修改语义¶
在历史上,对 locals()
的返回值进行修改的预期结果是保留给各个 Python 实现来定义的。
通过 PEP 667,Python 3.13 标准化了 CPython 对于大多数代码执行作用域的历史行为,但也将 已优化作用域 (函数、生成器、协程、推导式和生成器表达式) 修改为显式地返回当前已赋值局部变量的独立快照,包括局部引用的在闭包中捕获的非局部变量。
在已优化的作用域中对 locals()
语义的这项修改也会影响隐式地以 locals()
为目标的代码执行函数的默认行为,如果没有提供显式命名空间的话(例如 exec()
和 eval()
等)。 在之前的版本中,在调用代码执行函数后是否可以通过调用 locals()
访问更改情况取决于具体的实现。 具体到 CPython 而言,此类代码通常会按预期运作,但有时可能会在基于其他代码(包括调试器和代码执行跟踪工具)的已优化作用域中失败,因为代码有可能重置该作用域中的共享快照。 现在,代码在已优化作用域中将始终针对局部变量的独立快照运行,因此在后续调用 locals()
时将永远看不到更改。 要访问在这些情况下所做的更改,现在必须将一个显式命名空间引用传递给相关的函数。 或者,也可以更新受影响的代码以使用更高级别的代码执行 API 返回结果代码执行命名空间 (例如,当执行磁盘上的 Python 文件时使用 runpy.run_path()
函数)。
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未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。)
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。
对移动平台的支持¶
现在 iOS 是 PEP 11 支持的平台。
arm64-apple-ios
(2013 年之后发布的 iPhone 和 iPad 设备) 和arm64-apple-ios-simulator
(运行于 Apple Silicon 硬件之上的 Xcode iOS 模拟器) 现在是第 3 层级的平台。x86_64-apple-ios-simulator
(运行于较老的 x86_64 硬件之上的 Xcode iOS) 不是第 3 层级的受支持平台,但将会尽可能地提供支持。请参阅 PEP 730 了解详情。
(PEP 的撰写和实现由 Russell Keith-Magee 在 gh-114099 中贡献。)
实验性的 JIT 编译器¶
使用 --enable-experimental-jit
选项配置 CPython 时,会添加一个可以让部分 Python 程序提升速度的即时编译器。
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 第 2 层级 IR,即微操作码 ("uops")。
第 2 层级 IR 使用同一个基于栈的 VM 作为第 1 层级,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。
--enable-experimental-jit
旗标具有下列可选值:
no
(默认值) -- 禁用整个第 2 层级和 JIT 管线。yes
(当提供了该旗标但没有可选值时的默认值) -- 启用 JIT。 要在运行时禁用 JIT,请传入环境变量PYTHON_JIT=0
。yes-off
-- 构建 JIT 但默认禁用它。要在运行时启用 JIT,请传入环境变量PYTHON_JIT=1
。interpreter
-- 启用第 2 层级解释器,但是禁用 JIT。运行时传入PYTHON_JIT=0
可以禁用解释器。
(在 Windows 上,使用 PCbuild/build.bat --experimental-jit
启用 JIT,使用 --experimental-jit-interpreter
启用第 2 层级解释器。)
详见 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。)
自由线程的 CPython¶
在使用 --disable-gil
选项配置进行构建时,CPython 将在运行时禁用 global interpreter lock (GIL)。 这是一个实验性特性,因此默认将不使用。 用户需要编译自己的解释器,或者安装标记为 free-threaded 的实验性构建版。 请参阅 PEP 703 "Making the Global Interpreter Lock Optional in CPython" 了解详情。
自由线程允许通过在可用的 CPU 核心上并行运行线程来充分地利用可用的处理能力。虽然并非所有软件都会自动受益于此,但考虑到多线程设计的程序将在多核硬件上运行地更快。
工作仍在进行中:预计会出现一些错误和显著的单线程性能损失。
自由线程构建仍然支持在运行时使用环境变量 PYTHON_GIL
或命令行选项 -X gil
选择性地启用 GIL。
要检查当前解释器是否配置了 --disable-gil
,请使用 sysconfig.get_config_var("Py_GIL_DISABLED")
。要检查 GIL 是否在正在运行的进程中实际被禁用,可以使用 sys._is_gil_enabled()
函数。
C-API 扩展模块需要专门为自由线程构建而构建。支持在禁用 GIL 的情况下运行的扩展应使用 Py_mod_gil
插槽。使用单阶段初始化的扩展应使用 PyUnstable_Module_SetGIL()
来指示它们是否支持在禁用 GIL 的情况下运行。导入不使用这些机制的 C 扩展将导致启用 GIL,除非使用 PYTHON_GIL
环境变量或 -X gil=0
选项明确禁用 GIL。
需要 pip 24.1b1 或更新版本才能在自由线程构建中安装带有 C 扩展的包。
其他语言特性修改¶
允许
str.replace()
的 count 参数为关键字参数。 (由 Hugo van Kemenade 在 gh-106487 中贡献。)编译器现在会删除文档字符串中的缩进。 这将减少 字节码缓存 (即
.pyc
文件) 的大小。例如,SQLAlchemy 2.0 中sqlalchemy.orm.session
的缓存文件大小减少了约 5%。 此更改将影响使用文档字符串的工具,例如doctest
。 (由 Inada Naoki 在 gh-81283 中贡献。)compile()
内置函数现在可以接受新的旗标ast.PyCF_OPTIMIZED_AST
,它与ast.PyCF_ONLY_AST
类似,不同之处在于返回的AST
是根据optimize
参数的值进行优化的。(由 Irit Katriel 在 gh-108113 中贡献)。multiprocessing
、concurrent.futures
、compileall
:将os.cpu_count()
替换为os.process_cpu_count()
,以选择默认的工作线程和进程数。如果支持,则获取 CPU 亲和性。(由 Victor Stinner 在 gh-109649 中贡献。)即使文件不可访问,
os.path.realpath()
现在也能解析 MS-DOS 样式的文件名。(由 Moonsik Park 在 gh-82367 中贡献。)修复了当在
else
块中使用全局变量时except
块中的global
声明被拒绝的错误。(由 Irit Katriel 在 gh-111123 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。)
添加了新的环境变量
PYTHON_FROZEN_MODULES
。它决定导入机制是否忽略冻结模块,相当于-X frozen_modules
命令行选项。(由 Yilei Yang 在 gh-111374 中贡献。)添加无需帧指针即可工作的 性能分析器支持,可通过新的环境变量
PYTHON_PERF_JIT_SUPPORT
和命令行选项-X perf_jit <-X>`启用(由 Pablo Galindo 在 :gh:`118518
中贡献。)新的
PYTHON_HISTORY
环境变量可用于更改.python_history
文件的位置。(由 Levi Sabah、Zackery Spytz 和 Hugo van Kemenade 在 gh-73965 中贡献。)添加
PythonFinalizationError
异常。当操作在 解释器关闭 期间被阻止时,会抛出此派生自RuntimeError
的异常。下列函数现在会引发 PythonFinalizationError,而不是
RuntimeError
:(由 Victor Stinner 在 gh-114570 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。)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.sax.expatreader.ExpatParser.flush()
(由 Sebastian Pipping 在 gh-115623 中贡献。)
ssl.create_default_context()
API 现在默认包含ssl.VERIFY_X509_PARTIAL_CHAIN
和ssl.VERIFY_X509_STRICT
旗标。備註
ssl.VERIFY_X509_STRICT
可能会拒绝底层 OpenSSL 实现本来会接受的 RFC 5280 之前的证书或格式错误的证书。虽然不建议禁用此功能,但您可以使用以下方法禁用:ctx = ssl.create_default_context() ctx.verify_flags &= ~ssl.VERIFY_X509_STRICT
(由 William Woodruff 在 gh-112389 贡献。)
configparser.ConfigParser
现在可以被配置为在命名部分之前接受未命名部分。(由 Pedro Sousa Lacerda 在 gh-66449 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。位于类范围内的推导式不会内联到其父作用域中。(由 Jelle Zijlstra 在 gh-109118 和 gh-118160 中贡献。)
类有一个新的
__firstlineno__
属性,由编译器填充,其中包含类定义第一行的行号。(由 Serhiy Storchaka 在 gh-118465 中贡献。)现在如果模块名前有点,
from __future__ import ...
语句只是普通的相对导入。(由 Jeremiah Gabriel Pascual 在 gh-118216 中贡献。)
新增模块¶
无。
改进的模块¶
argparse¶
为
add_argument()
和add_parser()
方法添加了形参 deprecated 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¶
ast¶
现在
ast
模块中节点类型的构造器对其可接受的参数要求更严格,并在参数被省略时具有更易理解的行为。If an optional field on an AST node is not included as an argument when constructing an instance, the field will now be set to
None
. Similarly, if a list field is omitted, that field will now be set to an empty list, and if aast.expr_context
field is omitted, it defaults toLoad()
. (Previously, in all cases, the attribute would be missing on the newly constructed AST node instance.)If other arguments are omitted, a
DeprecationWarning
is emitted. This will cause an exception in Python 3.15. Similarly, passing a keyword argument that does not map to a field on the AST node is now deprecated, and will raise an exception in Python 3.15.These changes do not apply to user-defined subclasses of
ast.AST
, unless the class opts in to the new behavior by setting the attributeast.AST._field_types
.(Contributed by Jelle Zijlstra in gh-105858, gh-117486, and gh-118851.)
ast.parse()
now accepts an optional argument optimize which is passed on to thecompile()
built-in. This makes it possible to obtain an optimized AST. (Contributed by Irit Katriel in gh-108113.)
asyncio¶
asyncio.loop.create_unix_server()
will now automatically remove the Unix socket when the server is closed. (Contributed by Pierre Ossman in gh-111246.)asyncio.DatagramTransport.sendto()
will now send zero-length datagrams if called with an empty bytes object. The transport flow control also now accounts for the datagram header when calculating the buffer size. (Contributed by Jamie Phan in gh-115199.)Add
asyncio.Server.close_clients()
andasyncio.Server.abort_clients()
methods which allow to more forcefully close an asyncio server. (Contributed by Pierre Ossman in gh-113538.)asyncio.as_completed()
now returns an object that is both an asynchronous iterator and a plain iterator of awaitables. The awaitables yielded by asynchronous iteration include original task or future objects that were passed in, making it easier to associate results with the tasks being completed. (Contributed by Justin Arthur in gh-77714.)When
asyncio.TaskGroup.create_task()
is called on an inactiveasyncio.TaskGroup
, the given coroutine will be closed (which prevents aRuntimeWarning
about the given coroutine being never awaited). (Contributed by Arthur Tacca and Jason Zhang in gh-115957.)Improved behavior of
asyncio.TaskGroup
when an external cancellation collides with an internal cancellation. For example, when two task groups are nested and both experience an exception in a child task simultaneously, it was possible that the outer task group would hang, because its internal cancellation was swallowed by the inner task group.In the case where a task group is cancelled externally and also must raise an
ExceptionGroup
, it will now call the parent task'scancel()
method. This ensures that aasyncio.CancelledError
will be raised at the nextawait
, so the cancellation is not lost.An added benefit of these changes is that task groups now preserve the cancellation count (
asyncio.Task.cancelling()
).In order to handle some corner cases,
asyncio.Task.uncancel()
may now reset the undocumented_must_cancel
flag when the cancellation count reaches zero.(Inspired by an issue reported by Arthur Tacca in gh-116720.)
Add
asyncio.Queue.shutdown()
(along withasyncio.QueueShutDown
) for queue termination. (Contributed by Laurie Opperman and Yves Duprat in gh-104228.)Accept a tuple of separators in
asyncio.StreamReader.readuntil()
, stopping when one of them is encountered. (Contributed by Bruce Merry in gh-81322.)
base64¶
Add
base64.z85encode()
andbase64.z85decode()
functions which allow encoding and decoding Z85 data. See Z85 specification for more information. (Contributed by Matan Perelman in gh-75299.)
copy¶
Add
copy.replace()
function which allows to create a modified copy of an object, which is especially useful for immutable objects. It supports named tuples created with the factory functioncollections.namedtuple()
,dataclass
instances, variousdatetime
objects,Signature
objects,Parameter
objects, code object, and any user classes which define the__replace__()
method. (Contributed by Serhiy Storchaka in gh-108751.)
ctypes¶
The layout of bit fields in
Structure
andUnion
was improved to better match platform defaults (GCC/Clang or MSC). In particular, fields no longer overlap. (Contributed by Matthias Görgens in gh-97702.)A
ctypes.Structure._layout_
class attribute can be set to help match a non-default ABI. (Contributed by Petr Viktorin in gh-97702.)
dbm¶
Add
dbm.gnu.gdbm.clear()
anddbm.ndbm.ndbm.clear()
methods that remove all items from the database. (Contributed by Donghee Na in gh-107122.)Add new
dbm.sqlite3
backend, and make it the defaultdbm
backend. (Contributed by Raymond Hettinger and Erlend E. Aasland in gh-100414.)
dis¶
Change the output of
dis
module functions to show logical labels for jump targets and exception handlers, rather than offsets. The offsets can be added with the new-O
command line option or theshow_offsets
parameter. (Contributed by Irit Katriel in gh-112137.)get_instructions()
no longer represents cache entries as separate instructions. Instead, it returns them as part of theInstruction
, in the new cache_info field. The show_caches argument toget_instructions()
is deprecated and no longer has any effect. (Contributed by Irit Katriel in gh-112962.)
doctest¶
Color is added to the output by default. This can be controlled via the new
PYTHON_COLORS
environment variable as well as the canonicalNO_COLOR
andFORCE_COLOR
environment variables. See also 控制颜色. (Contributed by Hugo van Kemenade in gh-117225.)The
doctest.DocTestRunner.run()
method now counts the number of skipped tests. Adddoctest.DocTestRunner.skips
anddoctest.TestResults.skipped
attributes. (Contributed by Victor Stinner in gh-108794.)
email¶
email.utils.getaddresses()
andemail.utils.parseaddr()
now return('', '')
2-tuples in more situations where invalid email addresses are encountered instead of potentially inaccurate values. Add optional strict parameter to these two functions: usestrict=False
to get the old behavior, accept malformed inputs.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¶
Formatting for objects of type
fractions.Fraction
now supports the standard format specification mini-language rules for fill, alignment, sign handling, minimum width and grouping. (Contributed by Mark Dickinson in gh-111320.)
gc¶
The cyclic garbage collector is now incremental, which changes the meanings of the results of
gc.get_threshold()
andgc.set_threshold()
as well asgc.get_count()
andgc.get_stats()
.gc.get_threshold()
returns a three-item tuple for backwards compatibility. The first value is the threshold for young collections, as before; the second value determines the rate at which the old collection is scanned (the default is 10, and higher values mean that the old collection is scanned more slowly). The third value is meaningless and is always zero.gc.set_threshold()
ignores any items after the second.gc.get_count()
andgc.get_stats()
return the same format of results as before. The only difference is that instead of the results referring to the young, aging and old generations, the results refer to the young generation and the aging and collecting spaces of the old generation.
In summary, code that attempted to manipulate the behavior of the cycle GC may not work exactly as intended, but it is very unlikely to be harmful. All other code will work just fine.
glob¶
Add
glob.translate()
function that converts a path specification with shell-style wildcards to a regular expression. (Contributed by Barney Gale in gh-72904.)
importlib¶
Previously deprecated
importlib.resources
functions are un-deprecated:All now allow for a directory (or tree) of resources, using multiple positional arguments.
For text-reading functions, the encoding and errors must now be given as keyword arguments.
The
contents()
remains deprecated in favor of the full-featuredTraversable
API. However, there is now no plan to remove it.(Contributed by Petr Viktorin in gh-106532.)
io¶
The
io.IOBase
finalizer now logs theclose()
method errors withsys.unraisablehook
. Previously, errors were ignored silently by default, and only logged in Python Development Mode or on Python built on debug mode. (Contributed by Victor Stinner in gh-62948.)
ipaddress¶
Add the
ipaddress.IPv4Address.ipv6_mapped
property, which returns the IPv4-mapped IPv6 address. (Contributed by Charles Machalow in gh-109466.)Fix
is_global
andis_private
behavior inIPv4Address
,IPv6Address
,IPv4Network
andIPv6Network
.
itertools¶
Added a
strict
option toitertools.batched()
. This raises aValueError
if the final batch is shorter than the specified batch size. (Contributed by Raymond Hettinger in gh-113202.)
marshal¶
Add the allow_code parameter in module functions. Passing
allow_code=False
prevents serialization and de-serialization of code objects which are incompatible between Python versions. (Contributed by Serhiy Storchaka in gh-113626.)
math¶
A new function
fma()
for fused multiply-add operations has been added. This function computesx * y + z
with only a single round, and so avoids any intermediate loss of precision. It wraps thefma()
function provided by C99, and follows the specification of the IEEE 754 "fusedMultiplyAdd" operation for special cases. (Contributed by Mark Dickinson and Victor Stinner in gh-73468.)
mimetypes¶
Add the
guess_file_type()
function which works with file path. Passing file path instead of URL inguess_type()
is soft deprecated. (Contributed by Serhiy Storchaka in gh-66543.)
mmap¶
The
mmap.mmap
class now has anseekable()
method that can be used when a seekable file-like object is required. Theseek()
method now returns the new absolute position. (Contributed by Donghee Na and Sylvie Liberman in gh-111835.)mmap.mmap
now has a trackfd parameter on Unix; if it isFalse
, the file descriptor specified by fileno will not be duplicated. (Contributed by Zackery Spytz and Petr Viktorin in gh-78502.)mmap.mmap
is now protected from crashing on Windows when the mapped memory is inaccessible due to file system errors or access violations. (Contributed by Jannis Weigend in gh-118209.)
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 usage. (Contributed by Irit Katriel in gh-105481.)Removed
opcode.is_pseudo
,opcode.MIN_PSEUDO_OPCODE
andopcode.MAX_PSEUDO_OPCODE
, which were added in 3.12, were never documented or exposed throughdis
, and were not intended to be used externally.
os¶
Add
os.process_cpu_count()
function to get the number of logical CPUs usable by the calling thread of the current process. (Contributed by Victor Stinner in gh-109649.)Add a low level interface for Linux's timer notification file descriptors via
os.timerfd_create()
,os.timerfd_settime()
,os.timerfd_settime_ns()
,os.timerfd_gettime()
, andos.timerfd_gettime_ns()
,os.TFD_NONBLOCK
,os.TFD_CLOEXEC
,os.TFD_TIMER_ABSTIME
, andos.TFD_TIMER_CANCEL_ON_SET
(Contributed by Masaru Tsuchiyama in gh-108277.)os.cpu_count()
andos.process_cpu_count()
can be overridden through the new environment variablePYTHON_CPU_COUNT
or the new command-line option-X cpu_count
. This option is useful for users who need to limit CPU resources of a container system without having to modify the container (application code). (Contributed by Donghee Na in gh-109595.)Add support of
os.lchmod()
and the follow_symlinks argument inos.chmod()
on Windows. Note that the default value of follow_symlinks inos.lchmod()
isFalse
on Windows. (Contributed by Serhiy Storchaka in gh-59616.)Add support of
os.fchmod()
and a file descriptor inos.chmod()
on Windows. (Contributed by Serhiy Storchaka in gh-113191.)os.posix_spawn()
now acceptsenv=None
, which makes the newly spawned process use the current process environment. (Contributed by Jakub Kulik in gh-113119.)os.posix_spawn()
gains anos.POSIX_SPAWN_CLOSEFROM
attribute for use infile_actions=
on platforms that supportposix_spawn_file_actions_addclosefrom_np()
. (Contributed by Jakub Kulik in gh-113117.)os.mkdir()
andos.makedirs()
on Windows now support passing a mode value of0o700
to apply access control to the new directory. This implicitly affectstempfile.mkdtemp()
and is a mitigation for CVE-2024-4030. Other values for mode continue to be ignored. (Contributed by Steve Dower in gh-118486.)
os.path¶
Add
os.path.isreserved()
to check if a path is reserved on the current system. This function is only available on Windows. (Contributed by Barney Gale in gh-88569.)On Windows,
os.path.isabs()
no longer considers paths starting with exactly one (back)slash to be absolute. (Contributed by Barney Gale and Jon Foster in gh-44626.)Add support of dir_fd and follow_symlinks keyword arguments in
shutil.chown()
. (Contributed by Berker Peksag and Tahia K in gh-62308)
pathlib¶
Add
pathlib.UnsupportedOperation
, which is raised instead ofNotImplementedError
when a path operation isn't supported. (Contributed by Barney Gale in gh-89812.)Add
pathlib.Path.from_uri()
, a new constructor to create apathlib.Path
object from a 'file' URI (file://
). (Contributed by Barney Gale in gh-107465.)Add
pathlib.PurePath.full_match()
for matching paths with shell-style wildcards, including the recursive wildcard "**
". (Contributed by Barney Gale in gh-73435.)Add
pathlib.PurePath.parser
class attribute that stores the implementation ofos.path
used for low-level path parsing and joining: eitherposixpath
orntpath
.Add recurse_symlinks keyword-only argument to
pathlib.Path.glob()
andrglob()
. (Contributed by Barney Gale in gh-77609.)Add follow_symlinks keyword-only argument to
is_file()
,is_dir()
,owner()
,group()
. (Contributed by Barney Gale in gh-105793, and Kamil Turek in gh-107962.)Return files and directories from
pathlib.Path.glob()
andrglob()
when given a pattern that ends with "**
". In earlier versions, only directories were returned. (Contributed by Barney Gale in gh-70303.)
pdb¶
Add ability to move between chained exceptions during post mortem debugging in
pm()
using the newexceptions [exc_number]
command for Pdb. (Contributed by Matthias Bussonnier in gh-106676.)Expressions/statements whose prefix is a pdb command are now correctly identified and executed. (Contributed by Tian Gao in gh-108464.)
sys.path[0]
will no longer be replaced by the directory of the script being debugged whensys.flags.safe_path
is set (via the-P
command line option orPYTHONSAFEPATH
environment variable). (Contributed by Tian Gao and Christian Walther in gh-111762.)zipapp
is supported as a debugging target. (Contributed by Tian Gao in gh-118501.)breakpoint()
andpdb.set_trace()
now enter the debugger immediately rather than on the next line of code to be executed. This change prevents the debugger from breaking outside of the context whenbreakpoint()
is positioned at the end of the context. (Contributed by Tian Gao in gh-118579.)
queue¶
Add
queue.Queue.shutdown()
(along withqueue.ShutDown
) for queue termination. (Contributed by Laurie Opperman and Yves Duprat in gh-104750.)
random¶
Add a command-line interface. (Contributed by Hugo van Kemenade in gh-118131.)
re¶
Rename
re.error
tore.PatternError
for improved clarity.re.error
is kept for backward compatibility.
site¶
.pth
files are now decoded by UTF-8 first, and then by the locale encoding if the UTF-8 decoding fails. (Contributed by Inada Naoki in gh-117802.)
sqlite3¶
A
ResourceWarning
is now emitted if asqlite3.Connection
object is notclosed
explicitly. (Contributed by Erlend E. Aasland in gh-105539.)Add filter keyword-only parameter to
sqlite3.Connection.iterdump()
for filtering database objects to dump. (Contributed by Mariusz Felisiak in gh-91602.)
statistics¶
Add
statistics.kde()
for kernel density estimation. This makes it possible to estimate a continuous probability density function from a fixed number of discrete samples. Also addedstatistics.kde_random()
for sampling from the estimated probability density function. (Contributed by Raymond Hettinger in gh-115863.)
subprocess¶
The
subprocess
module now uses theos.posix_spawn()
function in more situations. Notably in the default case ofclose_fds=True
on more recent versions of platforms including Linux, FreeBSD, and Solaris where the C library providesposix_spawn_file_actions_addclosefrom_np()
. On Linux this should perform similar to our existing Linuxvfork()
based code. A private control knobsubprocess._USE_POSIX_SPAWN
can be set toFalse
if you need to forcesubprocess
not to ever useos.posix_spawn()
. Please report your reason and platform details in the CPython 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¶
Add the
sys._is_interned()
function to test if the string was interned. This function is not guaranteed to exist in all implementations of Python. (Contributed by Serhiy Storchaka in gh-78573.)
tempfile¶
On Windows, the default mode
0o700
used bytempfile.mkdtemp()
now limits access to the new directory due to changes toos.mkdir()
. This is a mitigation for CVE-2024-4030. (Contributed by Steve Dower in gh-118486.)
time¶
On Windows,
time.monotonic()
now uses theQueryPerformanceCounter()
clock to have a resolution better than 1 us, instead of theGetTickCount64()
clock which has a resolution of 15.6 ms. (Contributed by Victor Stinner in gh-88494.)On Windows,
time.time()
now uses theGetSystemTimePreciseAsFileTime()
clock to have a resolution better than 1 μs, instead of theGetSystemTimeAsFileTime()
clock which has a resolution of 15.6 ms. (Contributed by Victor Stinner in gh-63207.)
tkinter¶
Add
tkinter
widget methods:tk_busy_hold()
,tk_busy_configure()
,tk_busy_cget()
,tk_busy_forget()
,tk_busy_current()
, andtk_busy_status()
. (Contributed by Miguel, klappnase and Serhiy Storchaka in gh-72684.)The
tkinter
widget methodwm_attributes()
now accepts the attribute name without the minus prefix to get window attributes, e.g.w.wm_attributes('alpha')
and allows to specify attributes and values to set as keyword arguments, e.g.w.wm_attributes(alpha=0.5)
. Add new optional keyword-only parameter return_python_dict: callingw.wm_attributes(return_python_dict=True)
returns the attributes as a dict instead of a tuple. (Contributed by Serhiy Storchaka in gh-43457.)Add new optional keyword-only parameter return_ints in the
Text.count()
method. Passingreturn_ints=True
makes it always returning the single count as an integer instead of a 1-tuple orNone
. (Contributed by Serhiy Storchaka in gh-97928.)Add support of the "vsapi" element type in the
element_create()
method oftkinter.ttk.Style
. (Contributed by Serhiy Storchaka in gh-68166.)Add the
after_info()
method for Tkinter widgets. (Contributed by Cheryl Sabella in gh-77020.)Add the
PhotoImage
methodcopy_replace()
to copy a region from one image to other image, possibly with pixel zooming and/or subsampling. Add from_coords parameter toPhotoImage
methodscopy()
,zoom()
andsubsample()
. Add zoom and subsample parameters toPhotoImage
methodcopy()
. (Contributed by Serhiy Storchaka in gh-118225.)Add the
PhotoImage
methodsread()
to read an image from a file anddata()
to get the image data. Add background and grayscale parameters toPhotoImage
methodwrite()
. (Contributed by Serhiy Storchaka in gh-118271.)
回溯¶
Add show_group parameter to
traceback.TracebackException.format_exception_only()
to format the nested exceptions of aBaseExceptionGroup
instance, recursively. (Contributed by Irit Katriel in gh-105292.)Add the field exc_type_str to
TracebackException
, which holds a string display of the exc_type. Deprecate the field exc_type which holds the type object itself. Add parameter save_exc_type (defaultTrue
) to indicate whetherexc_type
should be saved. (Contributed by Irit Katriel in gh-112332.)
types¶
SimpleNamespace
constructor now allows specifying initial values of attributes as a positional argument which must be a mapping or an iterable of key-value pairs. (Contributed by Serhiy Storchaka in gh-108191.)
typing¶
Add
typing.get_protocol_members()
to return the set of members defining atyping.Protocol
. Addtyping.is_protocol()
to check whether a class is atyping.Protocol
. (Contributed by Jelle Zijlstra in gh-104873.)Add
typing.ReadOnly
, a special typing construct to mark an item of atyping.TypedDict
as read-only for type checkers. See PEP 705 for more details.Add
typing.NoDefault
, a sentinel object used to represent the defaults of some parameters in thetyping
module. (Contributed by Jelle Zijlstra in gh-116126.)
unicodedata¶
The Unicode database has been updated to version 15.1.0. (Contributed by James Gerity in gh-109559.)
venv¶
Add support for adding source control management (SCM) ignore files to 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 (
venv.EnvBuilder
andvenv.create()
), and opt-out via the CLI (using--without-scm-ignore-files
). (Contributed by Brett Cannon in gh-108125.)
warnings¶
The new
warnings.deprecated()
decorator provides a way to communicate deprecations to static type checkers and to warn on usage of deprecated classes and functions. A runtime deprecation warning may also be emitted when a decorated function or class is used at runtime. See PEP 702. (Contributed by Jelle Zijlstra in gh-104003.)
xml.etree.ElementTree¶
Add the
close()
method for the iterator returned byiterparse()
for explicit cleaning up. (Contributed by Serhiy Storchaka in gh-69893.)
zipimport¶
Gains support for ZIP64 format files. Everybody loves huge code right? (Contributed by Tim Hatch in gh-94146.)
性能优化¶
textwrap.indent()
is now ~30% faster than before for large input. (Contributed by Inada Naoki in gh-107369.)The
subprocess
module usesos.posix_spawn()
in more situations including the default whereclose_fds=True
on many modern platforms. This should provide a noteworthy performance increase launching processes on FreeBSD and Solaris. See the subprocess section above for details. (Contributed by Jakub Kulik in gh-113117.)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 onre
andcontextlib
. Other modules to enjoy import-time speedups includeimportlib.metadata
,threading
,enum
,functools
andemail.utils
. (Contributed by Alex Waygood, Shantanu Jain, Adam Turner, Daniel Hollas and others in gh-109653.)
被移除的模块与 API¶
PEP 594: 死电池(与其他模块移除)¶
PEP 594 从标准库移除了 19 个从 Python 3.11 起弃用的模块:
aifc
. (Contributed by Victor Stinner in gh-104773.)audioop
. (Contributed by Victor Stinner in gh-104773.)chunk
. (Contributed by Victor Stinner in gh-104773.)cgi
andcgitb
.cgi.FieldStorage
can typically be replaced withurllib.parse.parse_qsl()
forGET
andHEAD
requests, and theemail.message
module or multipart PyPI project forPOST
andPUT
.cgi.parse()
can be replaced by callingurllib.parse.parse_qs()
directly on the desired query string, except formultipart/form-data
input, which can be handled as described forcgi.parse_multipart()
.cgi.parse_header()
can be replaced with the functionality in theemail
package, which implements the same MIME RFCs. For example, withemail.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 theemail
package (e.g.email.message.EmailMessage
andemail.message.Message
) which implements the same MIME RFCs, or with the multipart PyPI project.
(Contributed by Victor Stinner in gh-104773.)
crypt
module and its private_crypt
extension. Thehashlib
module is a potential replacement for certain use cases. Otherwise, the following PyPI projects can be used:bcrypt: Modern password hashing for your software and your servers.
passlib: Comprehensive password hashing framework supporting over 30 schemes.
argon2-cffi: The secure Argon2 password hashing algorithm.
legacycrypt:
ctypes
wrapper to the POSIX crypt library call and associated functionality.crypt_r: Fork of the
crypt
module, wrapper to the crypt_r(3) library call and associated functionality.
(Contributed by Victor Stinner in gh-104773.)
imghdr
: use the projects filetype, puremagic, or python-magic instead. Thepuremagic.what()
function can be used to replace theimghdr.what()
function for all file formats that were supported byimghdr
. (Contributed by Victor Stinner in gh-104773.)mailcap
. Themimetypes
module provides an alternative. (Contributed by Victor Stinner in gh-104773.)msilib
. (Contributed by Zachary Ware in gh-104773.)nis
. (Contributed by Victor Stinner in gh-104773.)nntplib
: the nntplib PyPI project can be used instead. (Contributed by Victor Stinner in gh-104773.)ossaudiodev
: use the pygame project for audio playback. (Contributed by Victor Stinner in gh-104780.)pipes
: use thesubprocess
module instead. (Contributed by Victor Stinner in gh-104773.)sndhdr
: use the projects filetype, puremagic, or python-magic instead. (Contributed by Victor Stinner in gh-104773.)spwd
: the python-pam project can be used instead. (Contributed by Victor Stinner in gh-104773.)sunau
. (Contributed by Victor Stinner in gh-104773.)telnetlib
, use the projects telnetlib3 or Exscript instead. (Contributed by Victor Stinner in gh-104773.)uu
: thebase64
module is a modern alternative. (Contributed by Victor Stinner in gh-104773.)xdrlib
. (Contributed by Victor Stinner in gh-104773.)
Remove the
2to3
program and thelib2to3
module, deprecated in Python 3.11. (Contributed by Victor Stinner in gh-104780.)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.)
configparser¶
Remove the undocumented
configparser.LegacyInterpolation
class, deprecated in the docstring since Python 3.2, and with a deprecation warning since Python 3.11. (Contributed by Hugo van Kemenade in gh-104886.)
importlib¶
Remove deprecated
__getitem__()
access forimportlib.metadata.EntryPoint
objects. (Contributed by Jason R. Coombs in gh-113175.)
locale¶
Remove
locale.resetlocale()
function deprecated in Python 3.11: uselocale.setlocale(locale.LC_ALL, "")
instead. (Contributed by Victor Stinner in gh-104783.)
logging¶
logging
: Remove undocumented and untestedLogger.warn()
andLoggerAdapter.warn()
methods andlogging.warn()
function. Deprecated since Python 3.3, they were aliases to thelogging.Logger.warning()
method,logging.LoggerAdapter.warning()
method andlogging.warning()
function. (Contributed by Victor Stinner in gh-105376.)
pathlib¶
Remove support for using
pathlib.Path
objects as context managers. This functionality was deprecated and made a no-op in Python 3.9.
re¶
Remove undocumented, never working, and deprecated
re.template
function andre.TEMPLATE
flag (andre.T
alias). (Contributed by Serhiy Storchaka and Nikita Sobolev in gh-105687.)
turtle¶
Remove the
turtle.RawTurtle.settiltangle()
method, deprecated in docs since Python 3.1 and with a deprecation warning since Python 3.11. (Contributed by Hugo van Kemenade in gh-104876.)
typing¶
Namespaces
typing.io
andtyping.re
, deprecated in Python 3.8, are now removed. The items in those namespaces can be imported directly fromtyping
. (Contributed by Sebastian Rittau in gh-92871.)Remove support for the keyword-argument method of creating
typing.TypedDict
types, deprecated in Python 3.11. (Contributed by Tomas Roun in gh-104786.)
unittest¶
Remove the following
unittest
functions, deprecated in Python 3.11:unittest.findTestCases()
unittest.makeSuite()
unittest.getTestCaseNames()
请改用
TestLoader
方法:(Contributed by Hugo van Kemenade in gh-104835.)
Remove the untested and undocumented
unittest.TestProgram.usageExit()
method, deprecated in Python 3.11. (Contributed by Hugo van Kemenade in gh-104992.)
urllib¶
Remove cafile, capath and cadefault parameters of the
urllib.request.urlopen()
function, deprecated in Python 3.6: pass the context parameter instead. Usessl.SSLContext.load_cert_chain()
to load specific certificates, or letssl.create_default_context()
select the system's trusted CA certificates for you. (Contributed by Victor Stinner in gh-105382.)
webbrowser¶
Remove the untested and undocumented
webbrowser
MacOSX
class, deprecated in Python 3.11. Use theMacOSXOSAScript
class (introduced in Python 3.2) instead. (Contributed by Hugo van Kemenade in gh-104804.)Remove deprecated
webbrowser.MacOSXOSAScript._name
attribute. Usewebbrowser.MacOSXOSAScript.name
attribute instead. (Contributed by Nikita Sobolev in gh-105546.)
New Deprecations¶
Removed chained
classmethod
descriptors (introduced in gh-63272). This can no longer be used to wrap other descriptors such asproperty
. The core design of this feature was flawed and caused a number of downstream problems. To "pass-through" aclassmethod
, consider using the__wrapped__
attribute that was added in Python 3.10. (Contributed by Raymond Hettinger in gh-89519.)array
:array
's'u'
format code, deprecated in docs since Python 3.3, emitsDeprecationWarning
since 3.13 and will be removed in Python 3.16. Use the'w'
format code instead. (Contributed by Hugo van Kemenade in gh-80480.)ctypes
: Deprecate undocumentedctypes.SetPointerType()
andctypes.ARRAY()
functions. Replacectypes.ARRAY(item_type, size)
withitem_type * size
. (Contributed by Victor Stinner in gh-105733.)decimal
: Deprecate non-standard format specifier "N" fordecimal.Decimal
. It was not documented and only supported in the C implementation. (Contributed by Serhiy Storchaka in gh-89902.)dis
: Thedis.HAVE_ARGUMENT
separator is deprecated. Check membership inhasarg
instead. (Contributed by Irit Katriel in gh-109319.)帧对象: Calling
frame.clear()
on a suspended frame raisesRuntimeError
(as has always been the case for an executing frame). (Contributed by Irit Katriel in gh-79932.)getopt
andoptparse
modules: They are now soft deprecated: theargparse
module should be used for new projects. Previously, theoptparse
module was already deprecated, its removal was not scheduled, and no warnings was emitted: so there is no change in practice. (Contributed by Victor Stinner in gh-106535.)gettext
: Emit deprecation warning for non-integer numbers ingettext
functions and methods that consider plural forms even if the translation was not found. (Contributed by Serhiy Storchaka in gh-88434.)glob
: The undocumentedglob.glob0()
andglob.glob1()
functions are deprecated. Useglob.glob()
and pass a directory to its root_dir argument instead. (Contributed by Barney Gale in gh-117337.)http.server
:http.server.CGIHTTPRequestHandler
now emits aDeprecationWarning
as it will be removed in 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. This includes removal of the--cgi
flag to thepython -m http.server
command line in 3.15.mimetypes
: Passing file path instead of URL inguess_type()
is soft deprecated. Useguess_file_type()
instead. (Contributed by Serhiy Storchaka in gh-66543.)re
: Passing optional arguments maxsplit, count and flags in module-level functionsre.split()
,re.sub()
andre.subn()
as positional arguments is now deprecated. In future Python versions these parameters will be keyword-only. (Contributed by Serhiy Storchaka in gh-56166.)pathlib
:pathlib.PurePath.is_reserved()
is deprecated and scheduled for removal in Python 3.15. Useos.path.isreserved()
to detect reserved paths on Windows.platform
:java_ver()
is deprecated and will be removed in 3.15. It was largely untested, had a confusing API, and was only useful for Jython support. (Contributed by Nikita Sobolev in gh-116349.)pydoc
: Deprecate undocumentedpydoc.ispackage()
function. (Contributed by Zackery Spytz in gh-64020.)sqlite3
: Passing more than one positional argument tosqlite3.connect()
and thesqlite3.Connection
constructor is deprecated. The remaining parameters will become keyword-only in Python 3.15.Deprecate passing name, number of arguments, and the callable as keyword arguments for the following
sqlite3.Connection
APIs:已弃用通过关键字参数形式为下列
sqlite3.Connection
API 传入可调用对象:受影响的形参将在 Python 3.15 中成为仅限位置形参。
sys
:sys._enablelegacywindowsfsencoding()
function. Replace it with thePYTHONLEGACYWINDOWSFSENCODING
environment variable. (Contributed by Inada Naoki in gh-73427.)tarfile
: The undocumented and unusedtarfile
attribute oftarfile.TarFile
is deprecated and scheduled for removal in Python 3.16.traceback
: The field exc_type oftraceback.TracebackException
is deprecated. Use exc_type_str instead.-
Creating a
typing.NamedTuple
class using keyword arguments to denote the fields (NT = NamedTuple("NT", x=int, y=int)
) is deprecated, and will be disallowed in Python 3.15. Use the class-based syntax or the functional syntax instead. (Contributed by Alex Waygood in gh-105566.)When using the functional syntax to create a
typing.NamedTuple
class or atyping.TypedDict
class, failing to pass a value to the 'fields' parameter (NT = NamedTuple("NT")
orTD = TypedDict("TD")
) is deprecated. PassingNone
to the 'fields' parameter (NT = NamedTuple("NT", None)
orTD = TypedDict("TD", None)
) is also deprecated. Both will be disallowed in Python 3.15. To create a NamedTuple class with 0 fields, useclass NT(NamedTuple): pass
orNT = NamedTuple("NT", [])
. To create a TypedDict class with 0 fields, useclass TD(TypedDict): pass
orTD = TypedDict("TD", {})
. (Contributed by Alex Waygood in gh-105566 and gh-105570.)typing.no_type_check_decorator()
is deprecated, and scheduled for removal in Python 3.15. After eight years in thetyping
module, it has yet to be supported by any major type checkers. (Contributed by Alex Waygood in gh-106309.)typing.AnyStr
is deprecated. In Python 3.16, it will be removed fromtyping.__all__
, and aDeprecationWarning
will be emitted 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.)
自訂函式: Assignment to a function's
__code__
attribute where the new code object's type does not match the function's type, is deprecated. The different types are: plain function, generator, async generator and coroutine. (Contributed by Irit Katriel in gh-81137.)wave
: Deprecate thegetmark()
,setmark()
andgetmarkers()
methods of thewave.Wave_read
andwave.Wave_write
classes. They will 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
: The following features have been deprecated in documentation since Python 3.8, now cause aDeprecationWarning
to be emitted at runtime when they are accessed or used, and will be removed in Python 3.14:ast.Num
ast.Str
ast.Bytes
ast.NameConstant
ast.Ellipsis
请改用
ast.Constant
。 (由 Serhiy Storchaka 在 gh-90953 中贡献。)collections.abc
: Deprecatedcollections.abc.ByteString
. PreferSequence
orBuffer
. For use in typing, prefer a union, likebytes | bytearray
, orcollections.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
:__package__
and__cached__
will cease to be set or taken into consideration by the import system (gh-97879).importlib.abc
deprecated classes:importlib.abc.ResourceReader
importlib.abc.Traversable
importlib.abc.TraversableResources
使用
importlib.resources.abc
类代替:(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
: The default start method will change to a safer one on Linux, BSDs, and other non-macOS POSIX platforms where'fork'
is currently the default (gh-84559). Adding a runtime warning about this was deemed too disruptive as the majority of code is not expected to care. Use theget_context()
orset_start_method()
APIs to explicitly specify when your code requires'fork'
. See 上下文和启动方法.pathlib
:is_relative_to()
andrelative_to()
: passing additional arguments is deprecated.pkgutil
:find_loader()
andget_loader()
now raiseDeprecationWarning
; useimportlib.util.find_spec()
instead. (Contributed by Nikita Sobolev in gh-97850.)pty
:master_open()
: usepty.openpty()
.slave_open()
: usepty.openpty()
.
-
version
andversion_info
.execute()
andexecutemany()
if named placeholders are used and parameters is a sequence instead of adict
.date and datetime adapter, date and timestamp converter: see the
sqlite3
documentation for suggested replacement recipes.
types.CodeType
: Accessingco_lnotab
was deprecated in PEP 626 since 3.10 and was planned to be removed in 3.12, but it only got a properDeprecationWarning
in 3.12. May be removed in 3.14. (Contributed by Nikita Sobolev in gh-101866.)typing
:typing.ByteString
, deprecated since Python 3.9, now causes aDeprecationWarning
to be emitted when it is used.urllib
:urllib.parse.Quoter
is deprecated: it was not intended to be a public API. (Contributed by Gregory P. Smith in gh-88168.)
Python 3.15 中的待移除功能¶
http.server.CGIHTTPRequestHandler
will be removed along with its related--cgi
flag topython -m http.server
. It was obsolete and rarely used. No direct replacement exists. Anything is better than CGI to interface a web server with a request handler.locale
:locale.getdefaultlocale()
was deprecated in Python 3.11 and originally planned for removal in Python 3.13 (gh-90817), but removal has been postponed to Python 3.15. Uselocale.setlocale()
,locale.getencoding()
andlocale.getlocale()
instead. (Contributed by Hugo van Kemenade in gh-111187.)pathlib
:pathlib.PurePath.is_reserved()
is deprecated and scheduled for removal in Python 3.15. Useos.path.isreserved()
to detect reserved paths on Windows.platform
:java_ver()
is deprecated and will be removed in 3.15. It was largely untested, had a confusing API, and was only useful for Jython support. (Contributed by Nikita Sobolev in gh-116349.)threading
: Passing any arguments tothreading.RLock()
is now deprecated. C version allows any numbers of args and kwargs, but they are just ignored. Python version does not allow any arguments. All arguments will be removed fromthreading.RLock()
in Python 3.15. (Contributed by Nikita Sobolev in gh-102029.)-
The undocumented keyword argument syntax for creating
NamedTuple
classes (NT = NamedTuple("NT", x=int)
) is deprecated, and will be disallowed in 3.15. Use the class-based syntax or the functional syntax instead.When using the functional syntax to create a
NamedTuple
class, failing to pass a value to the fields parameter (NT = NamedTuple("NT")
) is deprecated. PassingNone
to the fields parameter (NT = NamedTuple("NT", None)
) is also deprecated. Both will be disallowed in Python 3.15. To create aNamedTuple
class with 0 fields, useclass NT(NamedTuple): pass
orNT = NamedTuple("NT", [])
.
typing.TypedDict
: When using the functional syntax to create aTypedDict
class, failing to pass a value to the fields parameter (TD = TypedDict("TD")
) is deprecated. PassingNone
to the fields parameter (TD = TypedDict("TD", None)
) is also deprecated. Both will be disallowed in Python 3.15. To create aTypedDict
class with 0 fields, useclass TD(TypedDict): pass
orTD = TypedDict("TD", {})
.wave
: Deprecate thegetmark()
,setmark()
andgetmarkers()
methods of thewave.Wave_read
andwave.Wave_write
classes. They will be removed in Python 3.15. (Contributed by Victor Stinner in gh-105096.)
Pending Removal in Python 3.16¶
array.array
'u'
type (wchar_t
): use the'w'
type instead (Py_UCS4
).
计划在未来版本中移除¶
下列 API 在更早的 Python 版本中已被弃用并将被移除,但目前还没有确定它们的移除日期。
argparse
: Nesting argument groups and nesting mutually exclusive groups are deprecated.-
~bool
, bitwise inversion on bool.bool(NotImplemented)
.Generators:
throw(type, exc, tb)
andathrow(type, exc, tb)
signature is deprecated: usethrow(exc)
andathrow(exc)
instead, the single argument signature.Currently Python accepts numeric literals immediately followed by keywords, for example
0in x
,1or x
,0if 1else 2
. It allows confusing and ambiguous expressions like[0x1for x in y]
(which can be interpreted as[0x1 for x in y]
or[0x1f or x in y]
). A syntax warning is raised if the numeric literal is immediately followed by one of keywordsand
,else
,for
,if
,in
,is
andor
. In a future release it will be changed to a syntax error. (gh-87999)Support for
__index__()
and__int__()
method returning non-int type: these methods will be required to return an instance of a strict subclass ofint
.Support for
__float__()
method returning a strict subclass offloat
: these methods will be required to return an instance offloat
.Support for
__complex__()
method returning a strict subclass ofcomplex
: these methods will be required to return an instance ofcomplex
.Delegation of
int()
to__trunc__()
method.
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
: use thecodeobject.co_lines()
method instead.-
utcnow()
: usedatetime.datetime.now(tz=datetime.UTC)
.utcfromtimestamp()
: usedatetime.datetime.fromtimestamp(timestamp, tz=datetime.UTC)
.
gettext
: Plural value must be an integer.-
load_module()
method: useexec_module()
instead.cache_from_source()
debug_override parameter is deprecated: use the optimization parameter instead.
-
EntryPoints
tuple interface.Implicit
None
on return values.
mailbox
: Use of StringIO input and text mode is deprecated, use BytesIO and binary mode instead.os
: Callingos.register_at_fork()
in multi-threaded process.pydoc.ErrorDuringImport
: A tuple value for exc_info parameter is deprecated, use an exception instance.re
: More strict rules are now applied for numerical group references and group names in regular expressions. Only sequence of ASCII digits is now accepted as a numerical reference. The group name in bytes patterns and replacement strings can now only contain ASCII letters and digits and underscore. (Contributed by Serhiy Storchaka in gh-91760.)sre_compile
,sre_constants
andsre_parse
modules.shutil
:rmtree()
's onerror parameter is deprecated in Python 3.12; use the onexc parameter instead.ssl
options and protocols:ssl.SSLContext
without protocol argument is deprecated.ssl.SSLContext
:set_npn_protocols()
andselected_npn_protocol()
are deprecated: use ALPN instead.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 parameter is deprecated and ignored.threading
methods:threading.Condition.notifyAll()
: usenotify_all()
.threading.Event.isSet()
: useis_set()
.threading.Thread.isDaemon()
,threading.Thread.setDaemon()
: usethreading.Thread.daemon
attribute.threading.Thread.getName()
,threading.Thread.setName()
: usethreading.Thread.name
attribute.threading.currentThread()
: usethreading.current_thread()
.threading.activeCount()
: usethreading.active_count()
.
unittest.IsolatedAsyncioTestCase
: it is deprecated to return a value that is notNone
from a test case.urllib.parse
deprecated functions:urlparse()
insteadsplitattr()
splithost()
splitnport()
splitpasswd()
splitport()
splitquery()
splittag()
splittype()
splituser()
splitvalue()
to_bytes()
urllib.request
:URLopener
andFancyURLopener
style of invoking requests is deprecated. Use newerurlopen()
functions and methods.wsgiref
:SimpleHandler.stdout.write()
should not do partial writes.xml.etree.ElementTree
: Testing the truth value of anElement
is deprecated. In a future release it it will always returnTrue
. Prefer explicitlen(elem)
orelem is not None
tests instead.zipimport.zipimporter.load_module()
is deprecated: useexec_module()
instead.
CPython Bytecode Changes¶
The oparg of
YIELD_VALUE
is now1
if the yield is part of a yield-from or await, and0
otherwise. The oparg ofRESUME
was changed to add a bit indicating whether 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¶
You no longer have to define the
PY_SSIZE_T_CLEAN
macro before includingPython.h
when using#
formats in format codes. APIs accepting the format codes always usePy_ssize_t
for#
formats. (Contributed by Inada Naoki in gh-104922.)The keywords parameter of
PyArg_ParseTupleAndKeywords()
andPyArg_VaParseTupleAndKeywords()
now has type char *const* in C and const char *const* in C++, instead of char**. It makes these functions compatible with arguments of type const char *const*, const char** or char *const* in C++ and char *const* in C without an explicit type cast. This can be overridden with thePY_CXX_CONST
macro. (Contributed by Serhiy Storchaka in gh-65210.)Add
PyImport_AddModuleRef()
: similar toPyImport_AddModule()
, but return a strong reference instead of a borrowed reference. (Contributed by Victor Stinner in gh-105922.)Add
PyWeakref_GetRef()
function: similar toPyWeakref_GetObject()
but returns a strong reference, orNULL
if the referent is no longer live. (Contributed by Victor Stinner in gh-105927.)Add
PyObject_GetOptionalAttr()
andPyObject_GetOptionalAttrString()
, variants ofPyObject_GetAttr()
andPyObject_GetAttrString()
which don't raiseAttributeError
if the attribute is not found. 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
PyMapping_GetOptionalItem()
andPyMapping_GetOptionalItemString()
: variants ofPyObject_GetItem()
andPyMapping_GetItemString()
which don't raiseKeyError
if the key is not found. These variants are more convenient and faster if the missing key should not be treated as a failure. (Contributed by Serhiy Storchaka in gh-106307.)Add fixed variants of functions which silently ignore errors:
PyObject_HasAttrStringWithError()
替代PyObject_HasAttrString()
。PyMapping_HasKeyStringWithError()
replacesPyMapping_HasKeyString()
.
New functions return not only
1
for true and0
for false, but also-1
for error.(Contributed by Serhiy Storchaka in gh-108511.)
If Python is built in debug mode or
with assertions
,PyTuple_SET_ITEM()
andPyList_SET_ITEM()
now check the index argument with an assertion. (Contributed by Victor Stinner in gh-106168.)Add
PyModule_Add()
function: similar toPyModule_AddObjectRef()
andPyModule_AddObject()
but always steals a reference to the value. (Contributed by Serhiy Storchaka in gh-86493.)Add
PyDict_GetItemRef()
andPyDict_GetItemStringRef()
functions: similar toPyDict_GetItemWithError()
but returning a strong reference instead of a borrowed reference. Moreover, these functions return -1 on error and so checkingPyErr_Occurred()
is not needed. (Contributed by Victor Stinner in gh-106004.)Added
PyDict_SetDefaultRef()
, which is similar toPyDict_SetDefault()
but returns a strong reference instead of a borrowed reference. This function returns-1
on error,0
on insertion, and1
if the key was already present in the dictionary. (Contributed by Sam Gross in gh-112066.)Add
PyDict_ContainsString()
function: same asPyDict_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.)Added
PyList_GetItemRef()
function: similar toPyList_GetItem()
but returns a strong reference instead of a borrowed reference.Add
Py_IsFinalizing()
function: check if the main Python interpreter is shutting down. (Contributed by Victor Stinner in gh-108014.)Add
PyLong_AsInt()
function: similar toPyLong_AsLong()
, but store the result in a C int instead of a C long. Previously, it was known as the private function_PyLong_AsInt()
(with an underscore prefix). (Contributed by Victor Stinner in gh-108014.)Python built with
configure
--with-trace-refs
(tracing references) now supports the Limited API. (Contributed by Victor Stinner in gh-108634.)Add
PyObject_VisitManagedDict()
andPyObject_ClearManagedDict()
functions which must be called by the traverse and clear functions of a type usingPy_TPFLAGS_MANAGED_DICT
flag. The pythoncapi-compat project can be used to get these functions on Python 3.11 and 3.12. (Contributed by Victor Stinner in gh-107073.)Add
PyUnicode_EqualToUTF8AndSize()
andPyUnicode_EqualToUTF8()
functions: compare Unicode object with a const char* UTF-8 encoded string and return true (1
) if they are equal, or false (0
) otherwise. These functions do not raise exceptions. (Contributed by Serhiy Storchaka in gh-110289.)Add
PyThreadState_GetUnchecked()
function: similar toPyThreadState_Get()
, but don't kill the process with a fatal error if it is NULL. The caller is responsible to check if the result is NULL. Previously, the function was private and known as_PyThreadState_UncheckedGet()
. (Contributed by Victor Stinner in gh-108867.)Add
PySys_AuditTuple()
function: similar toPySys_Audit()
, but pass event arguments as a Pythontuple
object. (Contributed by Victor Stinner in gh-85283.)PyArg_ParseTupleAndKeywords()
now supports non-ASCII keyword parameter names. (Contributed by Serhiy Storchaka in gh-110815.)Add
PyMem_RawMalloc()
,PyMem_RawCalloc()
,PyMem_RawRealloc()
andPyMem_RawFree()
to the limited C API (version 3.13). (Contributed by Victor Stinner in gh-85283.)Add
PySys_Audit()
andPySys_AuditTuple()
functions to the limited C API. (Contributed by Victor Stinner in gh-85283.)Add
PyErr_FormatUnraisable()
function: similar toPyErr_WriteUnraisable()
, but allow customizing the warning message. (Contributed by Serhiy Storchaka in gh-108082.)Add
PyList_Extend()
andPyList_Clear()
functions: similar to Pythonlist.extend()
andlist.clear()
methods. (Contributed by Victor Stinner in gh-111138.)Add
PyDict_Pop()
andPyDict_PopString()
functions: remove a key from a dictionary and optionally return the removed value. This is similar todict.pop()
, but without the default value and not raisingKeyError
if the key is missing. (Contributed by Stefan Behnel and Victor Stinner in gh-111262.)Add
Py_HashPointer()
function to hash a pointer. (Contributed by Victor Stinner in gh-111545.)Add
PyObject_GenericHash()
function that implements the default hashing function of a Python object. (Contributed by Serhiy Storchaka in gh-113024.)新增 PyTime C API:
PyTime_t
类型。PyTime_MIN
和PyTime_MAX
常量。新增函数:
(由 Victor Stinner 和 Petr Viktorin 在 gh-110850 中贡献。)
Add
PyLong_AsNativeBytes()
,PyLong_FromNativeBytes()
andPyLong_FromUnsignedNativeBytes()
functions to simplify converting between native integer types and Pythonint
objects. (Contributed by Steve Dower in gh-111140.)Add
PyType_GetFullyQualifiedName()
function to get the type's fully qualified name. Equivalent tof"{type.__module__}.{type.__qualname__}"
, ortype.__qualname__
iftype.__module__
is not a string or is equal to"builtins"
. (Contributed by Victor Stinner in gh-111696.)Add
PyType_GetModuleName()
function to get the type's module name. Equivalent to getting thetype.__module__
attribute. (Contributed by Eric Snow and Victor Stinner in gh-111696.)Add support for
%T
,%#T
,%N
and%#N
formats toPyUnicode_FromFormat()
: format the fully qualified name of an object type and of a type: callPyType_GetModuleName()
. See PEP 737 for more information. (Contributed by Victor Stinner in gh-111696.)Add
Py_GetConstant()
andPy_GetConstantBorrowed()
functions to get constants. For example,Py_GetConstant(Py_CONSTANT_ZERO)
returns a strong reference to the constant zero. (Contributed by Victor Stinner in gh-115754.)Add
PyType_GetModuleByDef()
to the limited C API (Contributed by Victor Stinner in gh-116936.)Add two new functions to the C-API,
PyRefTracer_SetTracer()
andPyRefTracer_GetTracer()
, that allows to track object creation and destruction the same way thetracemalloc
module does. (Contributed by Pablo Galindo in gh-93502.)Add
PyEval_GetFrameBuiltins()
,PyEval_GetFrameGlobals()
, andPyEval_GetFrameLocals()
to the C API. These replacements forPyEval_GetBuiltins()
,PyEval_GetGlobals()
, andPyEval_GetLocals()
return strong references rather than borrowed references. (Added as part of PEP 667.)Add
PyMutex
API, a lightweight mutex that occupies a single byte. ThePyMutex_Lock()
function will release the GIL (if currently held) if the operation needs to block. (Contributed by Sam Gross in gh-108724.)
构建变化¶
The
configure
option--with-system-libmpdec
now defaults toyes
. The bundled copy oflibmpdecimal
will be removed in Python 3.15.Autoconf 2.71 and aclocal 1.16.4 are now required to regenerate the
configure
script. (Contributed by Christian Heimes in gh-89886.)SQLite 3.15.2 or newer is required to build the
sqlite3
extension module. (Contributed by Erlend Aasland in gh-105875.)Python built with
configure
--with-trace-refs
(tracing references) is now ABI compatible with the Python release build and debug build. (Contributed by Victor Stinner in gh-108634.)Building CPython now requires a compiler with support for the C11 atomic library, GCC built-in atomic functions, or MSVC interlocked intrinsics.
The
errno
,fcntl
,grp
,md5
,pwd
,resource
,termios
,winsound
,_ctypes_test
,_multiprocessing.posixshmem
,_scproxy
,_stat
,_statistics
,_testconsole
,_testimportmultiple
and_uuid
C extensions are now built with the limited C API. (Contributed by Victor Stinner in gh-85283.)wasm32-wasi
is now a PEP 11 tier 2 platform. (Contributed by Brett Cannon in gh-115192.)wasm32-emscripten
is no longer a PEP 11 supported platform. (Contributed by Brett Cannon in gh-115192.)Python now bundles the mimalloc library. 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.)
On POSIX systems, the pkg-config (
.pc
) filenames now include the ABI flags. For example, the free-threaded build generatespython-3.13t.pc
and the debug build generatespython-3.13d.pc
.
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¶
An
OSError
is now raised bygetpass.getuser()
for any failure to retrieve a username, instead ofImportError
on non-Unix platforms orKeyError
on Unix platforms where the password database is empty.现在
threading
模块会预期_thread
模块具有_is_main_interpreter
属性。 它是一个不带参数的函数并会在当前解释器为主解释器时返回True
。Any library or application that provides a custom
_thread
module must provide_is_main_interpreter()
, just like the module's other "private" attributes. (See gh-112826.)mailbox.Maildir
now ignores files with a leading dot. (Contributed by Zackery Spytz in gh-65559.)pathlib.Path.glob()
andrglob()
now return both files and directories if a pattern that ends with "**
" is given, rather than directories only. Users may add a trailing slash to match only directories.The value of the
mode
attribute ofgzip.GzipFile
was changed from integer (1
or2
) to string ('rb'
or'wb'
). The value of themode
attribute of the readable file-like object returned byzipfile.ZipFile.open()
was changed from'r'
to'rb'
. (Contributed by Serhiy Storchaka in gh-115961.)
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 behaviour now requires explicit calls to update the initially returned dictionary with the results of subsequent calls tolocals()
. Code execution functions that implicitly targetlocals()
(such asexec
andeval
) 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 viaexec
oreval
) 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 withdict
or the proxy's.copy()
method. (Changed as part of PEP 667.)
C API 的变化¶
Python.h
no longer includes the<ieeefp.h>
standard header. It was included for thefinite()
function which is now provided by the<math.h>
header. It should now be included explicitly if needed. Remove also theHAVE_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 theclock()
andgmtime()
functions,<sys/select.h>
provides theselect()
function, and<sys/time.h>
provides thefutimes()
,gettimeofday()
andsetitimer()
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 providesoffsetof()
function, andsize_t
andptrdiff_t
types. Including<stddef.h>
explicitly was already needed by all other platforms, theHAVE_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
andPy_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
andPy_TRASHCAN_SAFE_END
were removed. They should be replaced by the new macrosPy_TRASHCAN_BEGIN
andPy_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.)Functions
PyDict_GetItem()
,PyDict_GetItemString()
,PyMapping_HasKey()
,PyMapping_HasKeyString()
,PyObject_HasAttr()
,PyObject_HasAttrString()
, andPySys_GetObject()
, which clear all errors which occurred when calling them, now report them usingsys.unraisablehook()
. You may replace them with other functions as recommended in the documentation. (Contributed by Serhiy Storchaka in gh-106672.)PyCode_GetFirstFree()
is an unstable API now and has been renamed toPyUnstable_Code_GetFirstFree()
. (Contributed by Bogdan Romanyuk in gh-115781.)
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 subsequentPyEval_GetLocals()
calls in that frame, asPyFrame_GetLocals()
,locals()
, andFrameType.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 toPyEval_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. (Changed as part of PEP 667.)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. withPyDict_Copy()
) or by calling the newPyEval_GetFrameLocals()
API. (Changed as part of PEP 667.)PyFrame_FastToLocals()
andPyFrame_FastToLocalsWithError()
no longer have any effect. Calling these functions has been redundant since Python 3.11, whenPyFrame_GetLocals()
was first introduced. (Changed as part of PEP 667.)PyFrame_LocalsToFast()
no longer has any effect. Calling this function is redundant now thatPyFrame_GetLocals()
returns a write-through proxy for optimized scopes. (Changed as part of PEP 667.)
Removed C APIs¶
Remove many APIs (functions, macros, variables) with names prefixed by
_Py
or_PY
(considered as private API). If your project is affected by one of these removals and you consider that the removed API should remain available, please open a new issue to request a public C API and addcc @vstinner
to the issue to notify Victor Stinner. (Contributed by Victor Stinner in gh-106320.)Remove functions deprecated in Python 3.9:
PyEval_CallObject()
,PyEval_CallObjectWithKeywords()
: usePyObject_CallNoArgs()
orPyObject_Call()
instead. Warning:PyObject_Call()
positional arguments must be atuple
and must not beNULL
, keyword arguments must be adict
orNULL
, whereas removed functions checked arguments type and acceptedNULL
positional and keyword arguments. To replacePyEval_CallObjectWithKeywords(func, NULL, kwargs)
withPyObject_Call()
, pass an empty tuple as positional arguments usingPyTuple_New(0)
.PyEval_CallFunction()
: usePyObject_CallFunction()
instead.PyEval_CallMethod()
: usePyObject_CallMethod()
instead.PyCFunction_Call()
: usePyObject_Call()
instead.
(Contributed by Victor Stinner in gh-105107.)
Remove old buffer protocols deprecated in Python 3.0. Use 緩衝協定 (Buffer Protocol) instead.
PyObject_CheckReadBuffer()
: UsePyObject_CheckBuffer()
to test if the object supports the buffer protocol. Note thatPyObject_CheckBuffer()
doesn't guarantee thatPyObject_GetBuffer()
will succeed. To test if the object is actually readable, see the next example ofPyObject_GetBuffer()
.PyObject_AsCharBuffer()
,PyObject_AsReadBuffer()
:PyObject_GetBuffer()
andPyBuffer_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()
: UsePyObject_GetBuffer()
andPyBuffer_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 the following old functions to configure the Python initialization, deprecated in Python 3.11:
PySys_AddWarnOptionUnicode()
: usePyConfig.warnoptions
instead.PySys_AddWarnOption()
: usePyConfig.warnoptions
instead.PySys_AddXOption()
: usePyConfig.xoptions
instead.PySys_HasWarnOptions()
: usePyConfig.xoptions
instead.PySys_SetPath()
: setPyConfig.module_search_paths
instead.Py_SetPath()
: setPyConfig.module_search_paths
instead.Py_SetStandardStreamEncoding()
: setPyConfig.stdio_encoding
instead, and set also maybePyConfig.legacy_windows_stdio
(on Windows)._Py_SetProgramFullPath()
: setPyConfig.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_ThreadsInitialized()
function, deprecated in Python 3.9. Since Python 3.7,Py_Initialize()
always creates the GIL: callingPyEval_InitThreads()
does nothing andPyEval_ThreadsInitialized()
always returned non-zero. (Contributed by Victor Stinner in gh-105182.)Remove
PyEval_AcquireLock()
andPyEval_ReleaseLock()
functions, deprecated in Python 3.2. They didn't update the current thread state. They can be replaced with:low-level
PyEval_AcquireThread()
andPyEval_RestoreThread()
;
(Contributed by Victor Stinner in gh-105182.)
Remove private
_PyObject_FastCall()
function: usePyObject_Vectorcall()
which is available since Python 3.8 (PEP 590). (Contributed by Victor Stinner in gh-106023.)Remove
cpython/pytime.h
header file: it only contained private functions. (Contributed by Victor Stinner in gh-106316.)Remove
_PyInterpreterState_Get()
alias toPyInterpreterState_Get()
which was kept for backward compatibility with Python 3.8. The pythoncapi-compat project can be used to getPyInterpreterState_Get()
on Python 3.8 and older. (Contributed by Victor Stinner in gh-106320.)The
PyModule_AddObject()
function is now soft deprecated:PyModule_Add()
orPyModule_AddObjectRef()
functions should be used instead. (Contributed by Serhiy Storchaka in gh-86493.)
Deprecated C APIs¶
Deprecate the old
Py_UNICODE
andPY_UNICODE_TYPE
types: use directly thewchar_t
type instead. Since Python 3.3,Py_UNICODE
andPY_UNICODE_TYPE
are just aliases towchar_t
. (Contributed by Victor Stinner in gh-105156.)Deprecate old Python initialization functions:
PySys_ResetWarnOptions()
: clearsys.warnoptions
andwarnings.filters
instead.Py_GetExecPrefix()
: getsys.exec_prefix
instead.Py_GetPath()
: getsys.path
instead.Py_GetPrefix()
: getsys.prefix
instead.Py_GetProgramFullPath()
: getsys.executable
instead.Py_GetProgramName()
: getsys.executable
instead.Py_GetPythonHome()
: getPyConfig.home
orPYTHONHOME
environment variable instead.
Functions scheduled for removal in Python 3.15. (Contributed by Victor Stinner in gh-105145.)
Deprecate the
PyImport_ImportModuleNoBlock()
function which is just an alias toPyImport_ImportModule()
since Python 3.3. Scheduled for removal in Python 3.15. (Contributed by Victor Stinner in gh-105396.)Deprecate the
PyWeakref_GetObject()
andPyWeakref_GET_OBJECT()
functions, which return a borrowed reference: use the newPyWeakref_GetRef()
function instead, it returns a strong reference. The pythoncapi-compat project can be used to getPyWeakref_GetRef()
on Python 3.12 and older. (Contributed by Victor Stinner in gh-105927.)Deprecate the
PyEval_GetBuiltins()
,PyEval_GetGlobals()
, andPyEval_GetLocals()
functions, which return a borrowed reference. Refer to the deprecation notices on each function for their recommended replacements. (Soft deprecated as part of PEP 667.)
计划在 Python 3.14 中移除¶
使用 C API 创建基于可变基类创建不可变类型 (
Py_TPFLAGS_IMMUTABLETYPE
)。用于配置 Python 初始化的函数,在 Python 3.11 中已弃用:
PySys_SetArgvEx()
: 改为设置PyConfig.argv
。PySys_SetArgv()
: 改为设置PyConfig.argv
。Py_SetProgramName()
: 改为设置PyConfig.program_name
。Py_SetPythonHome()
: 改为设置PyConfig.home
。
Py_InitializeFromConfig()
API 应与PyConfig
一起使用。全局配置变量:
Py_HashRandomizationFlag
: 使用PyConfig.use_hash_seed
和PyConfig.hash_seed
Py_LegacyWindowsFSEncodingFlag
: 使用PyPreConfig.legacy_windows_fs_encoding
Py_FileSystemDefaultEncoding
: 使用PyConfig.filesystem_encoding
Py_HasFileSystemDefaultEncoding
: 使用PyConfig.filesystem_encoding
Py_FileSystemDefaultEncodeErrors
: 使用PyConfig.filesystem_errors
Py_UTF8Mode
: 使用PyPreConfig.utf8_mode
(参见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。Py_UNICODE_WIDE
类型:改用wchar_t
。Py_UNICODE
类型:改用wchar_t
。Python 初始化函数
PySys_ResetWarnOptions()
: clearsys.warnoptions
andwarnings.filters
instead.Py_GetExecPrefix()
: getsys.exec_prefix
instead.Py_GetPath()
: getsys.path
instead.Py_GetPrefix()
: getsys.prefix
instead.Py_GetProgramFullPath()
: getsys.executable
instead.Py_GetProgramName()
: getsys.executable
instead.Py_GetPythonHome()
: getPyConfig.home
orPYTHONHOME
environment variable instead.
计划在未来版本中移除¶
下列 API 在更早的 Python 版本中已被弃用并将被移除,但目前还没有确定它们的移除日期。
Py_TPFLAGS_HAVE_FINALIZE
: 自 Python 3.8 起不再需要。PyUnicode_AsDecodedObject()
。PyUnicode_AsDecodedUnicode()
。PyUnicode_AsEncodedObject()
。PyUnicode_AsEncodedUnicode()
。PyUnicode_READY()
: 自 Python 3.12 起不再需要。_PyErr_ChainExceptions()
。PyBytesObject.ob_shash
成员:改为调用PyObject_Hash()
。PyDictObject.ma_version_tag
成员。TLS API:
从受限 C API 移除了未写入文档的
PY_TIMEOUT_MAX
常量。 (由 Victor Stinner 在 gh-110014 中贡献。)
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。)