3.13.0b1 - Cpython — ContextQMD

.. date: 2024-03-27-13-50-02 .. gh-issue: 116741 .. nonce: ZoGryG .. release date: 2024-05-08 .. section: Security

Update bundled libexpat to 2.6.2

.. date: 2024-03-25-21-25-28 .. gh-issue: 117233 .. nonce: E4CyI_ .. section: Security

Detect BLAKE2, SHA3, Shake, & truncated SHA512 support in the OpenSSL-ish libcrypto library at build time. This allows :mod:hashlib to be used with libraries that do not to support every algorithm that upstream OpenSSL does.

.. date: 2024-05-07-01-39-24 .. gh-issue: 118414 .. nonce: G5GG7l .. section: Core and Builtins

Add instrumented opcodes to YIELD_VALUE assertion for tracing cases.

.. date: 2024-05-06-10-57-54 .. gh-issue: 117953 .. nonce: DqCzIs .. section: Core and Builtins

When a builtin or extension module is imported for the first time, while a subinterpreter is active, the module's init function is now run by the main interpreter first before import continues in the subinterpreter. Consequently, single-phase init modules now fail in an isolated subinterpreter without the init function running under that interpreter, whereas before it would run under the subinterpreter before failing, potentially leaving behind global state and callbacks and otherwise leaving the module in an inconsistent state.

.. date: 2024-05-05-12-04-02 .. gh-issue: 117549 .. nonce: kITawD .. section: Core and Builtins

Don't use designated initializer syntax in inline functions in internal headers. They cause problems for C++ or MSVC users who aren't yet using the latest C++ standard (C++20). While internal, pycore_backoff.h, is included (indirectly, via pycore_code.h) by some key 3rd party software that does so for speed.

.. date: 2024-05-03-18-01-26 .. gh-issue: 95382 .. nonce: 73FSEv .. section: Library

Improve performance of :func:json.dumps and :func:json.dump when using the argument indent. Depending on the data the encoding using :func:json.dumps with indent can be up to 2 to 3 times faster.

.. date: 2024-05-03-17-49-37 .. gh-issue: 116322 .. nonce: Gy6M4j .. section: Core and Builtins

In --disable-gil builds, the GIL will be enabled while loading C extension modules. If the module indicates that it supports running without the GIL, the GIL will be disabled once loading is complete. Otherwise, the GIL will remain enabled for the remainder of the interpreter's lifetime. This behavior does not apply if the GIL has been explicitly enabled or disabled with PYTHON_GIL or -Xgil.

.. date: 2024-05-02-21-19-35 .. gh-issue: 118513 .. nonce: qHODjb .. section: Core and Builtins

Fix incorrect :exc:UnboundLocalError when two comprehensions in the same function both reference the same name, and in one comprehension the name is bound while in the other it's an implicit global.

.. date: 2024-05-02-20-32-42 .. gh-issue: 118518 .. nonce: m-JbTi .. section: Core and Builtins

Allow the Linux perf support to work without frame pointers using perf's advanced JIT support. The feature is activated when using the PYTHON_PERF_JIT_SUPPORT environment variable or when running Python with -Xperf_jit. Patch by Pablo Galindo.

.. date: 2024-05-02-16-04-51 .. gh-issue: 117514 .. nonce: CJiuC0 .. section: Core and Builtins

Add sys._is_gil_enabled() function that returns whether the GIL is currently enabled. In the default build it always returns True because the GIL is always enabled. In the free-threaded build, it may return True or False.

.. date: 2024-05-02-15-57-07 .. gh-issue: 118164 .. nonce: AF6kwI .. section: Core and Builtins

Break a loop between the Python implementation of the :mod:decimal module and the Python code for integer to string conversion. Also optimize integer to string conversion for values in the range from 9_000 to 135_000 decimal digits.

.. date: 2024-05-01-22-43-54 .. gh-issue: 118473 .. nonce: QIvq9R .. section: Core and Builtins

Fix :func:sys.set_asyncgen_hooks not to be partially set when raising :exc:TypeError.

.. date: 2024-05-01-17-12-36 .. gh-issue: 118465 .. nonce: g3Q8iE .. section: Core and Builtins

Compiler populates the new __firstlineno__ field on a class with the line number of the first line of the class definition.

.. date: 2024-05-01-14-20-28 .. gh-issue: 118492 .. nonce: VUsSfn .. section: Core and Builtins

Fix an issue where the type cache can expose a previously accessed attribute when a finalizer is run.

.. date: 2024-05-01-07-06-48 .. gh-issue: 117714 .. nonce: Ip_dm5 .. section: Core and Builtins

update async_generator.athrow().close() and async_generator.asend().close() to close their section of the underlying async generator

.. date: 2024-04-28-00-41-17 .. gh-issue: 111201 .. nonce: cQsh5U .. section: Core and Builtins

The :term:interactive interpreter is now implemented in Python, which allows for a number of new features like colors, multiline input, history viewing, and paste mode. Contributed by Pablo Galindo, Łukasz Langa and Lysandros Nikolaou based on code from the PyPy project.

.. date: 2024-04-27-21-44-40 .. gh-issue: 74929 .. nonce: C2nESp .. section: Core and Builtins

Implement PEP 667: converted :attr:FrameType.f_locals <frame.f_locals> and :c:func:PyFrame_GetLocals to return a write-through proxy object when the frame refers to a function or comprehension.

.. date: 2024-04-27-16-23-29 .. gh-issue: 116767 .. nonce: z9UFpr .. section: Core and Builtins

Fix crash in compiler on 'async with' that has many context managers.

.. date: 2024-04-26-14-06-18 .. gh-issue: 118335 .. nonce: SRFsxO .. section: Core and Builtins

Change how to use the tier 2 interpreter. Instead of running Python with -X uops or setting the environment variable PYTHON_UOPS=1, this choice is now made at build time by configuring with --enable-experimental-jit=interpreter.

Beware! This changes the environment variable to enable or disable micro-ops to PYTHON_JIT. The old PYTHON_UOPS is no longer used.

.. date: 2024-04-26-05-38-18 .. gh-issue: 118306 .. nonce: vRUEOU .. section: Core and Builtins

Update JIT compilation to use LLVM 18

.. date: 2024-04-25-21-18-19 .. gh-issue: 118160 .. nonce: GH5SMc .. section: Core and Builtins

:ref:Annotation scopes <annotation-scopes> within classes can now contain comprehensions. However, such comprehensions are not inlined into their parent scope at runtime. Patch by Jelle Zijlstra.

.. date: 2024-04-25-12-55-47 .. gh-issue: 118272 .. nonce: 5ptjk_ .. section: Core and Builtins

Fix bug where generator.close does not free the generator frame's locals.

.. date: 2024-04-25-11-48-28 .. gh-issue: 118216 .. nonce: SVg700 .. section: Core and Builtins

Don't consider :mod:__future__ imports with dots before the module name.

.. date: 2024-04-22-08-34-28 .. gh-issue: 118074 .. nonce: 5_JnIa .. section: Core and Builtins

Make sure that the Executor objects in the COLD_EXITS array aren't assumed to be GC-able (which would access bytes outside the object).

.. date: 2024-04-20-20-30-15 .. gh-issue: 107674 .. nonce: GZPOP7 .. section: Core and Builtins

Lazy load frame line number to improve performance of tracing

.. date: 2024-04-19-11-59-57 .. gh-issue: 118082 .. nonce: _FLuOT .. section: Core and Builtins

Improve :exc:SyntaxError message for imports without names, like in from x import and import cases. It now points out to users that :keyword:import expects at least one name after it.

.. date: 2024-04-19-11-57-46 .. gh-issue: 118090 .. nonce: eGAQ0B .. section: Core and Builtins

Improve :exc:SyntaxError message for empty type param brackets.

.. date: 2024-04-18-03-49-41 .. gh-issue: 117958 .. nonce: -EsfUs .. section: Core and Builtins

Added a get_jit_code() method to access JIT compiled machine code from the UOp Executor when the experimental JIT is enabled. Patch by Anthony Shaw.

.. date: 2024-04-17-22-53-52 .. gh-issue: 117901 .. nonce: SsEcVJ .. section: Core and Builtins

Add option for compiler's codegen to save nested instruction sequences for introspection.

.. date: 2024-04-17-22-49-15 .. gh-issue: 116622 .. nonce: tthNUF .. section: Core and Builtins

Redirect stdout and stderr to system log when embedded in an Android app.

.. date: 2024-04-17-17-52-32 .. gh-issue: 109118 .. nonce: q9iPEI .. section: Core and Builtins

:ref:annotation scope <annotation-scopes> within class scopes can now contain lambdas.

.. date: 2024-04-15-13-53-59 .. gh-issue: 117894 .. nonce: 8LpZ6m .. section: Core and Builtins

Prevent agen.aclose() objects being re-used after .throw().

.. date: 2024-04-15-07-37-09 .. gh-issue: 117881 .. nonce: 07H0wI .. section: Core and Builtins

prevent concurrent access to an async generator via athrow().throw() or asend().throw()

.. date: 2024-04-13-16-55-53 .. gh-issue: 117536 .. nonce: xkVbfv .. section: Core and Builtins

Fix a :exc:RuntimeWarning when calling agen.aclose().throw(Exception).

.. date: 2024-04-12-12-28-49 .. gh-issue: 117755 .. nonce: 6ct8kU .. section: Core and Builtins

Fix mimalloc allocator for huge memory allocation (around 8,589,934,592 GiB) on s390x. Patch by Victor Stinner.

.. date: 2024-04-12-11-19-18 .. gh-issue: 117750 .. nonce: YttK6h .. section: Core and Builtins

Fix issue where an object's dict would get out of sync with the object's internal values when being cleared. obj.__dict__.clear() now clears the internal values, but leaves the dict attached to the object.

.. date: 2024-04-12-09-09-11 .. gh-issue: 117431 .. nonce: lxFEeJ .. section: Core and Builtins

Improve the performance of the following :class:bytes and :class:bytearray methods by adapting them to the :c:macro:METH_FASTCALL calling convention:

:meth:!count
:meth:!find
:meth:!index
:meth:!rfind
:meth:!rindex

.. date: 2024-04-10-22-16-18 .. gh-issue: 117709 .. nonce: -_1YL0 .. section: Core and Builtins

Speed up calls to :func:str with positional-only argument, by using the :pep:590 vectorcall calling convention. Patch by Erlend Aasland.

.. date: 2024-04-09-16-07-00 .. gh-issue: 117680 .. nonce: MRZ78K .. section: Core and Builtins

Give _PyInstructionSequence a Python interface and use it in tests.

.. date: 2024-04-09-11-31-25 .. gh-issue: 115776 .. nonce: 5Nthd0 .. section: Core and Builtins

Statically allocated objects are, by definition, immortal so must be marked as such regardless of whether they are in extension modules or not.

.. date: 2024-03-30-00-37-53 .. gh-issue: 117385 .. nonce: h0OJti .. section: Core and Builtins

Remove unhandled PY_MONITORING_EVENT_BRANCH and PY_MONITORING_EVENT_EXCEPTION_HANDLED events from :func:sys.settrace.

.. date: 2024-03-12-13-51-09 .. gh-issue: 116322 .. nonce: q8TcDQ .. section: Core and Builtins

Extension modules may indicate to the runtime that they can run without the GIL. Multi-phase init modules do so by calling providing Py_MOD_GIL_NOT_USED for the Py_mod_gil slot, while single-phase init modules call PyUnstable_Module_SetGIL(mod, Py_MOD_GIL_NOT_USED) from their init function.

.. date: 2024-02-29-18-55-45 .. gh-issue: 116129 .. nonce: wsFnIq .. section: Core and Builtins

Implement :pep:696, adding support for defaults on type parameters. Patch by Jelle Zijlstra.

.. date: 2024-02-26-13-14-52 .. gh-issue: 93502 .. nonce: JMWRvA .. section: Core and Builtins

Add two new functions to the C-API, :c:func:PyRefTracer_SetTracer and :c:func:PyRefTracer_GetTracer, that allows to track object creation and destruction the same way the :mod:tracemalloc module does. Patch by Pablo Galindo

.. date: 2024-02-04-07-45-29 .. gh-issue: 107674 .. nonce: q8mCmi .. section: Core and Builtins

Improved the performance of :func:sys.settrace significantly

.. date: 2024-01-07-03-38-34 .. gh-issue: 95754 .. nonce: aPjEBG .. section: Core and Builtins

Improve the error message when a script shadowing a module from the standard library causes :exc:AttributeError to be raised. Similarly, improve the error message when a script shadowing a third party module attempts to access an attribute from that third party module while still initialising.

.. date: 2023-12-03-18-21-59 .. gh-issue: 99180 .. nonce: 5m0V0q .. section: Core and Builtins

Elide uninformative traceback indicators in return and simple assignment statements. Patch by Pablo Galindo.

.. date: 2023-06-18-00-27-57 .. gh-issue: 105879 .. nonce: dPw78k .. section: Core and Builtins

Allow the globals and locals arguments to :func:exec and :func:eval to be passed as keywords.

.. date: 2024-05-07-11-23-11 .. gh-issue: 118418 .. nonce: QPMdJm .. section: Library

A :exc:DeprecationWarning is now emitted if you fail to pass a value to the new type_params parameter of typing._eval_type() or typing.ForwardRef._evaluate(). (Using either of these private and undocumented functions is discouraged to begin with, but failing to pass a value to the type_params parameter may lead to incorrect behaviour on Python 3.12 or newer.)

.. date: 2024-05-06-18-13-02 .. gh-issue: 118660 .. nonce: n01Vb7 .. section: Library

Add an optional second type parameter to :class:typing.ContextManager and :class:typing.AsyncContextManager, representing the return types of :meth:~object.__exit__ and :meth:~object.__aexit__ respectively. This parameter defaults to bool | None.

.. date: 2024-05-06-16-52-40 .. gh-issue: 118650 .. nonce: qKz5lp .. section: Library

The enum module allows method named _repr_* to be defined on Enum types.

.. date: 2024-05-06-08-23-01 .. gh-issue: 118648 .. nonce: OVA3jJ .. section: Library

Add type parameter defaults to :class:typing.Generator and :class:typing.AsyncGenerator.

.. date: 2024-05-05-16-08-03 .. gh-issue: 101137 .. nonce: 71ECXu .. section: Library

Mime type text/x-rst is now supported by :mod:mimetypes.

.. date: 2024-05-04-20-22-59 .. gh-issue: 118164 .. nonce: 9D02MQ .. section: Library

The Python implementation of the decimal module could appear to hang in relatively small power cases (like 2**117) if context precision was set to a very high value. A different method to check for exactly representable results is used now that doesn't rely on computing 10**precision (which could be effectively too large to compute).

.. date: 2024-05-04-18-40-43 .. gh-issue: 111744 .. nonce: nuCtwN .. section: Library

breakpoint() and pdb.set_trace() now enter the debugger immediately after the call rather than before the next line is executed.

.. date: 2024-05-02-04-27-12 .. gh-issue: 118500 .. nonce: pBGGtQ .. section: Library

Add :mod:pdb support for zipapps

.. date: 2024-04-30-15-18-19 .. gh-issue: 118406 .. nonce: y-GnMo .. section: Library

Add signature for :class:sqlite3.Connection objects.

.. date: 2024-04-30-12-59-04 .. gh-issue: 101732 .. nonce: 29zUDu .. section: Library

Use a Y2038 compatible openssl time function when available.

.. date: 2024-04-29-22-11-54 .. gh-issue: 118404 .. nonce: GYfMaD .. section: Library

Fix :func:inspect.signature for non-comparable callables.

.. date: 2024-04-29-21-51-28 .. gh-issue: 118402 .. nonce: Z_06Th .. section: Library

Fix :func:inspect.signature for the result of the :func:functools.cmp_to_key call.

.. date: 2024-04-27-20-34-56 .. gh-issue: 116622 .. nonce: YlQgXv .. section: Library

On Android, :any:sysconfig.get_platform now returns the format specified by :pep:738.

.. date: 2024-04-26-14-53-28 .. gh-issue: 118285 .. nonce: A0_pte .. section: Library

Allow to specify the signature of custom callable instances of extension type by the __text_signature__ attribute. Specify signatures of :class:operator.attrgetter, :class:operator.itemgetter, and :class:operator.methodcaller instances.

.. date: 2024-04-26-12-42-29 .. gh-issue: 118314 .. nonce: Z7reGc .. section: Library

Fix an edge case in :func:binascii.a2b_base64 strict mode, where excessive padding is not detected when no padding is necessary.

.. date: 2024-04-25-11-49-11 .. gh-issue: 118271 .. nonce: 5N2Xcy .. section: Library

Add the :class:!PhotoImage methods :meth:!read to read an image from a file and :meth:!data to get the image data. Add background and grayscale parameters to :class:!PhotoImage method :meth:!write.

.. date: 2024-04-24-16-07-26 .. gh-issue: 118225 .. nonce: KdrcgL .. section: Library

Add the :class:!PhotoImage method :meth:!copy_replace to copy a region from one image to other image, possibly with pixel zooming and/or subsampling. Add from_coords parameter to :class:!PhotoImage methods :meth:!copy, :meth:!zoom and :meth:!subsample. Add zoom and subsample parameters to :class:!PhotoImage method :meth:!copy.

.. date: 2024-04-24-12-29-33 .. gh-issue: 118221 .. nonce: 2k_bac .. section: Library

Fix a bug where :meth:sqlite3.Connection.iterdump could fail if a custom :attr:row factory <sqlite3.Connection.row_factory> was used. Patch by Erlend Aasland.

.. date: 2024-04-24-12-20-48 .. gh-issue: 118013 .. nonce: TKn_kZ .. section: Library

Fix regression introduced in gh-103193 that meant that calling :func:inspect.getattr_static on an instance would cause a strong reference to that instance's class to persist in an internal cache in the :mod:inspect module. This caused unexpected memory consumption if the class was dynamically created, the class held strong references to other objects which took up a significant amount of memory, and the cache contained the sole strong reference to the class. The fix for the regression leads to a slowdown in :func:!getattr_static, but the function should still be significantly faster than it was in Python 3.11. Patch by Alex Waygood.

.. date: 2024-04-24-07-45-08 .. gh-issue: 118218 .. nonce: m1OHbN .. section: Library

Speed up :func:itertools.pairwise in the common case by up to 1.8x.

.. date: 2024-04-23-21-17-00 .. gh-issue: 117486 .. nonce: ea3KYD .. section: Library

Improve the behavior of user-defined subclasses of :class:ast.AST. Such classes will now require no changes in the usual case to conform with the behavior changes of the :mod:ast module in Python 3.13. Patch by Jelle Zijlstra.

.. date: 2024-04-22-21-54-12 .. gh-issue: 90848 .. nonce: 5jHEEc .. section: Library

Fixed :func:unittest.mock.create_autospec to configure parent mock with keyword arguments.

.. date: 2024-04-22-20-42-29 .. gh-issue: 118168 .. nonce: Igni7h .. section: Library

Fix incorrect argument substitution when :data:typing.Unpack is used with the builtin :class:tuple. :data:!typing.Unpack now raises :exc:TypeError when used with certain invalid types. Patch by Jelle Zijlstra.

.. date: 2024-04-21-18-55-42 .. gh-issue: 118131 .. nonce: eAT0is .. section: Library

Add command-line interface for the :mod:random module. Patch by Hugo van Kemenade.

.. date: 2024-04-19-09-28-43 .. gh-issue: 118107 .. nonce: Mdsr1J .. section: Library

Fix :mod:zipimport reading of ZIP64 files with file entries that are too big or offset too far.

.. date: 2024-04-19-08-50-48 .. gh-issue: 102511 .. nonce: qDEB66 .. section: Library

Fix :func:os.path.normpath for UNC paths on Windows. Speed up :func:os.path.splitroot with a native implementation.

.. date: 2024-04-18-00-35-11 .. gh-issue: 117535 .. nonce: 0m6SIM .. section: Library

Change the unknown filename of :mod:warnings from sys to <sys> to clarify that it's not a real filename.

.. date: 2024-04-17-22-00-15 .. gh-issue: 114053 .. nonce: _JBV4D .. section: Library

Fix erroneous :exc:NameError when calling :func:typing.get_type_hints on a class that made use of :pep:695 type parameters in a module that had from __future__ import annotations at the top of the file. Patch by Alex Waygood.

.. date: 2024-04-17-21-28-24 .. gh-issue: 116931 .. nonce: _AS09h .. section: Library

Add parameter fileobj check for :func:tarfile.TarFile.addfile

.. date: 2024-04-17-19-41-59 .. gh-issue: 117995 .. nonce: Vt76Rv .. section: Library

Don't raise :exc:DeprecationWarning when a :term:sequence of parameters is used to bind indexed, nameless placeholders. See also :gh:100668.

.. date: 2024-04-17-18-00-30 .. gh-issue: 80361 .. nonce: RstWg- .. section: Library

Fix TypeError in :func:email.message.Message.get_payload when the charset is :rfc:2231 encoded.

.. date: 2024-04-16-18-34-11 .. gh-issue: 86650 .. nonce: Zeydyg .. section: Library

Fix IndexError when parse some emails with invalid Message-ID (including one-off addresses generated by Microsoft Outlook).

.. date: 2024-04-14-15-59-28 .. gh-issue: 117691 .. nonce: 1mtREE .. section: Library

Improve the error messages emitted by :mod:tarfile deprecation warnings relating to PEP 706. If a filter argument is not provided to extract() or extractall, the deprecation warning now points to the line in the user's code where the relevant function was called. Patch by Alex Waygood.

.. date: 2024-04-13-18-59-25 .. gh-issue: 115874 .. nonce: c3xG-E .. section: Library

Fixed a possible segfault during garbage collection of _asyncio.FutureIter objects. Patch by Savannah Ostrowski.

.. date: 2024-04-13-01-45-15 .. gh-issue: 115060 .. nonce: IxoM03 .. section: Library

Speed up :meth:pathlib.Path.glob by omitting an initial :meth:~pathlib.Path.is_dir call. As a result of this change, :meth:~pathlib.Path.glob can no longer raise :exc:OSError.

.. date: 2024-04-12-17-37-11 .. gh-issue: 77102 .. nonce: Mk6X_E .. section: Library

:mod:site module now parses .pth file with UTF-8 first, and :term:locale encoding if UnicodeDecodeError happened. It supported only locale encoding before.

.. date: 2024-04-11-18-11-37 .. gh-issue: 76785 .. nonce: BWNkhC .. section: Library

We've exposed the low-level :mod:!_interpreters module for the sake of the PyPI implementation of :pep:734. It was sometimes available as the :mod:!_xxsubinterpreters module and was formerly used only for testing. For the most part, it should be considered an internal module, like :mod:!_thread and :mod:!_imp. See https://discuss.python.org/t/pep-734-multiple-interpreters-in-the-stdlib/41147/26.

.. date: 2024-04-10-22-35-24 .. gh-issue: 115060 .. nonce: XEVuOb .. section: Library

Speed up :meth:pathlib.Path.glob by not scanning directories for non-wildcard pattern segments.

.. date: 2024-04-10-21-30-37 .. gh-issue: 117727 .. nonce: uAYNVS .. section: Library

Speed up :meth:pathlib.Path.iterdir by using :func:os.scandir internally.

.. date: 2024-04-10-21-08-32 .. gh-issue: 117586 .. nonce: UCL__1 .. section: Library

Speed up :meth:pathlib.Path.walk by working with strings internally.

.. date: 2024-04-10-20-59-10 .. gh-issue: 117722 .. nonce: oxIUEI .. section: Library

Change the new multi-separator support in :meth:asyncio.StreamReader.readuntil to only accept tuples of separators rather than arbitrary iterables.

.. date: 2024-04-09-23-22-21 .. gh-issue: 117692 .. nonce: EciInD .. section: Library

Fixes a bug when :class:doctest.DocTestFinder was failing on wrapped builtin_function_or_method.

.. date: 2024-04-09-20-14-44 .. gh-issue: 117348 .. nonce: A2NAAz .. section: Library

Largely restored import time performance of configparser by avoiding dataclasses.

.. date: 2024-04-08-19-30-38 .. gh-issue: 117641 .. nonce: oaBGSJ .. section: Library

Speedup :func:os.path.commonpath on Unix.

.. date: 2024-04-08-19-12-26 .. gh-issue: 117663 .. nonce: CPfc_p .. section: Library

Fix _simple_enum to detect aliases when multiple arguments are present but only one is the member value.

.. date: 2024-04-08-14-33-38 .. gh-issue: 117636 .. nonce: exnRKd .. section: Library

Speedup :func:os.path.join.

.. date: 2024-04-08-03-23-22 .. gh-issue: 117618 .. nonce: -4DCUw .. section: Library

Support package.module as filename for break command of :mod:pdb

.. date: 2024-04-07-19-39-20 .. gh-issue: 102247 .. nonce: h8rqiX .. section: Library

the status codes enum with constants in http.HTTPStatus are updated to include the names from RFC9110. This RFC includes some HTTP statuses previously only used for WEBDAV and assigns more generic names to them.

The old constants are preserved for backwards compatibility.

.. date: 2024-04-07-18-42-09 .. gh-issue: 117607 .. nonce: C978BD .. section: Library

Speedup :func:os.path.relpath.

.. date: 2024-04-06-20-31-09 .. gh-issue: 117586 .. nonce: UgWdRK .. section: Library

Speed up :meth:pathlib.Path.glob by working with strings internally.

.. date: 2024-04-06-18-41-36 .. gh-issue: 117225 .. nonce: tJh1Hw .. section: Library

Add colour to doctest output. Patch by Hugo van Kemenade.

.. date: 2024-04-05-15-51-01 .. gh-issue: 117566 .. nonce: 54nABf .. section: Library

:meth:ipaddress.IPv6Address.is_loopback will now return True for IPv4-mapped loopback addresses, i.e. addresses in the ::ffff:127.0.0.0/104 address space.

.. date: 2024-04-05-13-38-53 .. gh-issue: 117546 .. nonce: lWjhHE .. section: Library

Fix issue where :func:os.path.realpath stopped resolving symlinks after encountering a symlink loop on POSIX.

.. date: 2024-04-04-15-28-12 .. gh-issue: 116720 .. nonce: aGhXns .. section: Library

Improved behavior of :class: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 misbehave, 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 :exc:ExceptionGroup, it will now call the parent task's :meth:~asyncio.Task.cancel method. This ensures that a :exc:asyncio.CancelledError will be raised at the next :keyword:await, so the cancellation is not lost.

An added benefit of these changes is that task groups now preserve the cancellation count (:meth:asyncio.Task.cancelling).

In order to handle some corner cases, :meth:asyncio.Task.uncancel may now reset the undocumented _must_cancel flag when the cancellation count reaches zero.

.. date: 2024-04-03-16-01-31 .. gh-issue: 117516 .. nonce: 7DlHje .. section: Library

Add :data:typing.TypeIs, implementing :pep:742. Patch by Jelle Zijlstra.

.. date: 2024-04-03-15-04-23 .. gh-issue: 117503 .. nonce: NMfwup .. section: Library

Fix support of non-ASCII user names in bytes paths in :func:os.path.expanduser on Posix.

.. date: 2024-04-02-11-17-44 .. gh-issue: 117394 .. nonce: 2aoSlb .. section: Library

:func:os.path.ismount is now 2-3 times faster if the user has permissions.

.. date: 2024-03-29-15-14-51 .. gh-issue: 117313 .. nonce: ks_ONu .. section: Library

Only treat '\n', '\r' and '\r\n' as line separators in re-folding the :mod:email messages. Preserve control characters '\v', '\f', '\x1c', '\x1d' and '\x1e' and Unicode line separators '\x85', '\u2028' and '\u2029' as is.

.. date: 2024-03-29-12-21-40 .. gh-issue: 117142 .. nonce: U0agfh .. section: Library

Convert :mod:!_ctypes to multi-phase initialisation (:pep:489).

.. date: 2024-03-26-15-29-39 .. gh-issue: 66543 .. nonce: OZBhU5 .. section: Library

Add the :func:mimetypes.guess_file_type function which works with file path. Passing file path instead of URL in :func:~mimetypes.guess_type is :term:soft deprecated.

.. date: 2024-03-20-00-11-39 .. gh-issue: 68583 .. nonce: mIlxxb .. section: Library

webbrowser CLI: replace getopt with argparse, add long options. Patch by Hugo van Kemenade.

.. date: 2024-03-17-18-24-23 .. gh-issue: 116871 .. nonce: 9uSl8M .. section: Library

Name suggestions for :exc:AttributeError and :exc:ImportError now only include underscored names if the original name was underscored.

.. date: 2024-02-28-11-51-51 .. gh-issue: 116023 .. nonce: CGYhFh .. section: Library

Don't show empty fields (value None or []) in :func:ast.dump by default. Add show_empty=False parameter to optionally show them.

.. date: 2024-02-28-10-41-24 .. gh-issue: 115961 .. nonce: P-_DU0 .. section: Library

Added :attr:!name and :attr:!mode attributes for compressed and archived file-like objects in modules :mod:bz2, :mod:lzma, :mod:tarfile and :mod:zipfile. The value of the :attr:!mode attribute of :class:gzip.GzipFile was changed from integer (1 or 2) to string ('rb' or 'wb'). The value of the :attr:!mode attribute of the readable file-like object returned by :meth:zipfile.ZipFile.open was changed from 'r' to 'rb'.

.. date: 2024-02-11-07-31-43 .. gh-issue: 82062 .. nonce: eeS6w7 .. section: Library

Fix :func:inspect.signature to correctly handle parameter defaults on methods in extension modules that use names defined in the module namespace.

.. date: 2024-01-19-05-40-46 .. gh-issue: 83856 .. nonce: jN5M80 .. section: Library

Honor :mod:atexit for all :mod:multiprocessing start methods

.. date: 2023-12-14-02-51-38 .. gh-issue: 113081 .. nonce: S-9Qyn .. section: Library

Print colorized exception just like built-in traceback in :mod:pdb

.. date: 2023-12-07-20-05-54 .. gh-issue: 112855 .. nonce: ph4ehh .. section: Library

Speed up pickling of :class:pathlib.PurePath objects. Patch by Barney Gale.

.. date: 2023-11-07-22-41-42 .. gh-issue: 111744 .. nonce: TbLxF0 .. section: Library

Support opcode events in :mod:bdb

.. date: 2023-10-24-12-39-04 .. gh-issue: 109617 .. nonce: YoI8TV .. section: Library

:mod:!ncurses: fixed a crash that could occur on macOS 13 or earlier when Python was built with Apple Xcode 15's SDK.

.. date: 2023-10-20-03-50-17 .. gh-issue: 83151 .. nonce: bcsD40 .. section: Library

Enabled arbitrary statements and evaluations in :mod:pdb shell to access the local variables of the current frame, which made it possible for multi-scope code like generators or nested function to work.

.. date: 2023-10-02-10-35-58 .. gh-issue: 110209 .. nonce: b5zfIz .. section: Library

Add :meth:~object.__class_getitem__ to :class:types.GeneratorType and :class:types.CoroutineType for type hinting purposes. Patch by James Hilton-Balfe.

.. date: 2023-08-21-10-34-43 .. gh-issue: 108191 .. nonce: GZM3mv .. section: Library

The :class:types.SimpleNamespace now accepts an optional positional argument which specifies initial values of attributes as a dict or an iterable of key-value pairs.

.. date: 2023-05-28-11-25-18 .. gh-issue: 62090 .. nonce: opAhDn .. section: Library

Fix assertion errors caused by whitespace in metavars or SUPPRESS-ed groups in :mod:argparse by simplifying usage formatting. Patch by Ali Hamdan.

.. date: 2023-03-03-21-13-08 .. gh-issue: 102402 .. nonce: fpkRO1 .. section: Library

Adjust logging.LogRecord to use time.time_ns() and fix minor bug related to floating-point math.

.. date: 2022-12-14-15-53-38 .. gh-issue: 100242 .. nonce: Ny7VUO .. section: Library

Bring pure Python implementation functools.partial.__new__ more in line with the C-implementation by not just always checking for the presence of the attribute 'func' on the first argument of partial. Instead, both the Python version and the C version perform an isinstance(func, partial) check on the first argument of partial.

.. date: 2022-11-23-17-16-31 .. gh-issue: 99730 .. nonce: bDQdaX .. section: Library

HEAD requests are no longer upgraded to GET request during redirects in urllib.

.. date: 2022-10-24-12-05-19 .. gh-issue: 66410 .. nonce: du4UKW .. section: Library

Setting the :mod:!tkinter module global :data:!wantobjects to 2 before creating the :class:~tkinter.Tk object or call the :meth:!wantobjects method of the :class:!Tk object with argument 2 makes now arguments to callbacks registered in the :mod:tkinter module to be passed as various Python objects (int, float, bytes, tuple), depending on their internal representation in Tcl, instead of always str. :data:!tkinter.wantobjects is now set to 2 by default.

.. bpo: 40943 .. date: 2020-06-10-19-24-17 .. nonce: vjiiN_ .. section: Library

Fix several IndexError when parse emails with truncated Message-ID, address, routes, etc, e.g. example@.

.. bpo: 39324 .. date: 2020-01-14-09-46-51 .. nonce: qUcDrM .. section: Library

Add mime type mapping for .md <-> text/markdown

.. bpo: 18108 .. date: 2019-09-09-18-18-34 .. nonce: ajPLAO .. section: Library

:func:shutil.chown now supports dir_fd and follow_symlinks keyword arguments.

.. bpo: 30988 .. date: 2019-08-29-20-26-08 .. nonce: b-_h5O .. section: Library

Fix parsing of emails with invalid address headers having a leading or trailing dot. Patch by tsufeki.

.. bpo: 32839 .. date: 2018-02-13-10-02-54 .. nonce: McbVz3 .. section: Library

Add the :meth:!after_info method for Tkinter widgets.

.. date: 2024-04-25-22-12-20 .. gh-issue: 117928 .. nonce: LKdTno .. section: Documentation

The minimum Sphinx version required for the documentation is now 6.2.1.

.. date: 2024-05-07-21-15-47 .. gh-issue: 118734 .. nonce: --GHiS .. section: Build

Fixes Windows build when invoked directly (not through the :file:build.bat script) without specifying a value for UseTIER2.

.. date: 2024-05-06-00-39-06 .. gh-issue: 115119 .. nonce: LT27pF .. section: Build

The :file:configure option :option:--with-system-libmpdec now defaults to yes. The bundled copy of libmpdecimal will be removed in Python 3.15.

.. date: 2024-04-15-08-35-06 .. gh-issue: 117845 .. nonce: IowzyW .. section: Build

Fix building against recent libedit versions by detecting readline hook signatures in :program:configure.

.. date: 2024-04-14-19-35-35 .. gh-issue: 116622 .. nonce: 8lpX-7 .. section: Build

A testbed project was added to run the test suite on Android.

.. date: 2024-04-09-12-59-06 .. gh-issue: 117645 .. nonce: 0oEVAa .. section: Build

Increase WASI stack size from 512 KiB to 8 MiB and the initial memory from 10 MiB to 20 MiB. Patch by Victor Stinner.

.. date: 2024-02-13-15-31-28 .. gh-issue: 115119 .. nonce: FnQzAW .. section: Build

:program:configure now uses :program:pkg-config to detect :mod:decimal dependencies if the :option:--with-system-libmpdec option is given.

.. date: 2024-05-02-09-28-04 .. gh-issue: 115119 .. nonce: cUKMXo .. section: Windows

Update Windows installer to use libmpdecimal 4.0.0.

.. date: 2024-05-01-20-57-09 .. gh-issue: 118486 .. nonce: K44KJG .. section: Windows

:func:os.mkdir now accepts mode of 0o700 to restrict the new directory to the current user.

.. date: 2024-04-29-13-53-25 .. gh-issue: 118347 .. nonce: U5ZRm_ .. section: Windows

Fixes launcher updates not being installed.

.. date: 2024-04-26-14-23-07 .. gh-issue: 118293 .. nonce: ohhPtW .. section: Windows

The multiprocessing module now passes the STARTF_FORCEOFFFEEDBACK flag when spawning processes to tell Windows not to change the mouse cursor.

.. date: 2024-04-15-21-23-34 .. gh-issue: 115009 .. nonce: uhisHP .. section: Windows

Update Windows installer to use SQLite 3.45.3.

.. date: 2024-04-12-14-02-58 .. gh-issue: 90329 .. nonce: YpEeaO .. section: Windows

Suppress the warning displayed on virtual environment creation when the requested and created paths differ only by a short (8.3 style) name. Warnings will continue to be shown if a junction or symlink in the path caused the venv to be created in a different location than originally requested.

.. date: 2024-04-12-13-18-42 .. gh-issue: 117786 .. nonce: LpI01s .. section: Windows

Fixes virtual environments not correctly launching when created from a Store install.

.. date: 2024-05-03-12-13-27 .. gh-issue: 115119 .. nonce: ltDtoR .. section: macOS

Update macOS installer to use libmpdecimal 4.0.0.

.. date: 2024-04-19-08-40-00 .. gh-issue: 114099 .. nonce: _iDfrQ .. section: macOS

iOS preprocessor symbol usage was made compatible with older macOS SDKs.

.. date: 2024-04-15-21-19-39 .. gh-issue: 115009 .. nonce: IdxH9N .. section: macOS

Update macOS installer to use SQLite 3.45.3.

.. date: 2022-04-17-01-07-42 .. gh-issue: 91629 .. nonce: YBGAAt .. section: macOS

Use :file:~/.config/fish/conf.d configs and :program:fish_add_path to set :envvar:PATH when installing for the Fish shell.

.. bpo: 34774 .. date: 2018-09-23-01-36-39 .. nonce: VeM-X- .. section: IDLE

Use user-selected color theme for Help => IDLE Doc.

.. date: 2024-04-29-17-44-15 .. gh-issue: 118124 .. nonce: czQQ9G .. section: C API

Fix :c:macro:Py_BUILD_ASSERT and :c:macro:Py_BUILD_ASSERT_EXPR for non-constant expressions: use static_assert() on C11 and newer. Patch by Victor Stinner.

.. date: 2024-04-29-17-19-07 .. gh-issue: 110850 .. nonce: vcpLn1 .. section: C API

Add "Raw" variant of PyTime functions

:c:func:PyTime_MonotonicRaw
:c:func:PyTime_PerfCounterRaw
:c:func:PyTime_TimeRaw

Patch by Victor Stinner.

.. date: 2024-04-17-16-48-17 .. gh-issue: 117987 .. nonce: zsvNL1 .. section: C API

Restore functions removed in Python 3.13 alpha 1:

:c:func:Py_SetPythonHome
:c:func:Py_SetProgramName
:c:func:PySys_SetArgvEx
:c:func:PySys_SetArgv

Patch by Victor Stinner.

.. date: 2024-04-16-13-34-01 .. gh-issue: 117929 .. nonce: HSr419 .. section: C API

Restore removed :c:func:PyEval_InitThreads function. Patch by Victor Stinner.

.. date: 2024-04-08-09-44-29 .. gh-issue: 117534 .. nonce: 54ZE_n .. section: C API

Improve validation logic in the C implementation of :meth:datetime.datetime.fromisoformat to better handle invalid years. Patch by Vlad Efanov.

.. date: 2024-03-18-17-29-52 .. gh-issue: 68114 .. nonce: W7R_lI .. section: C API

Fixed skipitem()'s handling of the old 'w' and 'w#' formatters. These are no longer supported and now raise an exception if used.

.. date: 2024-03-13-17-48-24 .. gh-issue: 111997 .. nonce: 8ZbHlA .. section: C API

Add a C-API for firing monitoring events.