Python 3.12.0 alpha 1

Release date: 2022-10-25

安全性

• gh-97616 [https://github.com/python/cpython/issues/97616]: Fix multiplying a list by an integer (list *= int): detect the integer overflow when the new allocated length is close to the maximum size. Issue reported by Jordan Limor. Patch by Victor Stinner.

• gh-97514 [https://github.com/python/cpython/issues/97514]: On Linux the multiprocessing module returns to using filesystem backed unix domain sockets for communication with the forkserver process instead of the Linux abstract socket namespace. Only code that chooses to use the "forkserver" start method is affected.

Abstract sockets have no permissions and could allow any user on the system in the same network namespace [https://man7.org/linux/manpages/man7/network_namespaces.7.html] (often the whole system) to inject code into the multiprocessing forkserver process. This was a potential privilege escalation. Filesystem based socket permissions restrict this to the forkserver process user as was the default in Python 3.8 and earlier.

This prevents Linux CVE 2022-42919 [https://www.cve.org/CVERecord?id=CVE-2022-42919].

• gh-87389 [https://github.com/python/cpython/issues/87389]: http.server: Fix an open redirection vulnerability in the HTTP server when an URI path starts with //. Vulnerability discovered, and initial fix proposed, by Hamza Avvan.

• gh-79096 [https://github.com/python/cpython/issues/79096]: LWPCookieJar and MozillaCookieJar create files with file mode 600 instead of 644 (Microsoft Windows is not affected)

• gh-92888 [https://github.com/python/cpython/issues/92888]: Fix memoryview use after free when accessing the backing buffer in certain cases.

• gh-68966 [https://github.com/python/cpython/issues/68966]: The deprecated mailcap module now refuses to inject unsafe text (filenames, MIME types, parameters) into shell commands. Instead of using such text, it will warn and act as if a match was not found (or for test commands, as if the test failed).

核心与内置函数

• gh-98374 [https://github.com/python/cpython/issues/98374]: Suppress ImportError for invalid query for help() command. Patch by Donghee Na.

• gh-98461 [https://github.com/python/cpython/issues/98461]: Fix source location in bytecode for list, set and dict comprehensions as well as generator expressions.

• gh-98354 [https://github.com/python/cpython/issues/98354]: Added unicode check for name attribute of spec argument passed in imp.createbuiltin() function.

• gh-98398 [https://github.com/python/cpython/issues/98398]: Fix source location of 'assert' bytecodes.

• gh-98390 [https://github.com/python/cpython/issues/98390]: Fix location of subexpressions of boolean expressions, by reducing their scope to that of the subexpression.

• gh-98254 [https://github.com/python/cpython/issues/98254]: Modules from the standard library are now potentially suggested as part of the error messages displayed by the interpreter when an NameError is raised to the top level. Patch by Pablo Galindo

• gh-97997 [https://github.com/python/cpython/issues/97997]: Add running column offset to the tokenizer state to avoid calculating AST column information with pointer arithmetic.

• gh-97973 [https://github.com/python/cpython/issues/97973]: Modify the tokenizer to return all necessary information the parser needs to set location information in the AST nodes, so that the parser does not have to calculate those doing pointer arithmetic.

• gh-96078 [https://github.com/python/cpython/issues/96078]: os.sched_yield() now release the GIL while calling sched_yield(2). Patch by Donghee Na.

• gh-97955 [https://github.com/python/cpython/issues/97955]: Migrate zoneinfo to Argument Clinic.

• gh-97912 [https://github.com/python/cpython/issues/97912]: The compiler now avoids quadratic behavior when finding which instructions should use the LOAD_FAST_CHECK opcode.

• gh-97002 [https://github.com/python/cpython/issues/97002]: Fix an issue where several frame objects could be backed by the same interpreter frame, possibly leading to corrupted memory and hard crashes of the interpreter.

• gh-97943 [https://github.com/python/cpython/issues/97943]: Bugfix: PyFunction_GetAnnotations() should return a borrowed reference. It was returning a new reference.

• gh-97922 [https://github.com/python/cpython/issues/97922]: The Garbage Collector now runs only on the eval breaker mechanism of the Python bytecode evaluation loop instead on object allocations. The GC can also run when PyErr_CheckSignals() is called so C extensions that need to run for a long time without executing any Python code also have a chance to execute the GC periodically.

• gh-65961 [https://github.com/python/cpython/issues/65961]: When __package__ is different than __spec__.parent, raise a DeprecationWarning instead of ImportWarning.

Also remove importlib.util.set_package() which was scheduled for removal.

• gh-97850 [https://github.com/python/cpython/issues/97850]: Long deprecated, module_repr() should now be completely eradicated.

• gh-86298 [https://github.com/python/cpython/issues/86298]: In cases where warnings.warn_explicit() consults the module's loader, an DeprecationWarning is issued when m.__loader__ differs from m.__spec__.loader.

• gh-97779 [https://github.com/python/cpython/issues/97779]: Ensure that all Python frame objects are backed by "complete" frames.

• gh-91052 [https://github.com/python/cpython/issues/91052]: Add API for subscribing to modification events on selected dictionaries.

• gh-97752 [https://github.com/python/cpython/issues/97752]: Fix possible data corruption or crashes when accessing the f_back member of newly-created generator or coroutine frames.

• gh-97591 [https://github.com/python/cpython/issues/97591]: Fixed a missing incref/decref pair in Exception.__setstate__(). Patch by Ofey Chan.

• gh-97670 [https://github.com/python/cpython/issues/97670]: Remove the sys.getdxp() function and the Tools/scripts/analyze_dxp.py script. DXP stands for "dynamic execution pairs". They were related to DYNAMIC_EXECUTION_PROFILE and DXPAIRS macros which have been removed in Python 3.11. Python can now be built with ./configure --enable-pystats to gather statistics on Python opcodes. Patch by Victor Stinner.

• gh-94526 [https://github.com/python/cpython/issues/94526]: Fix the Python path configuration used to initialized sys.path at Python startup. Paths are no longer encoded to UTF-8/strict to avoid encoding errors if it contains surrogate characters (bytes paths are decoded with the surrogateescape error handler). Patch by Victor Stinner.

• gh-96670 [https://github.com/python/cpython/issues/96670]: The parser now raises SyntaxError when parsing source code containing null bytes. Patch by Pablo Galindo

• gh-96975 [https://github.com/python/cpython/issues/96975]: Fix a crash occurring when PyEval_GetFrame() is called while the topmost Python frame is in a partially-initialized state.

• gh-96848 [https://github.com/python/cpython/issues/96848]: Fix command line parsing: reject -X int_max_str_digits option with no value (invalid) when the PYTHONINTMAXSTRDIGITS environment variable is set to a valid limit. Patch by Victor Stinner.

• gh-95921 [https://github.com/python/cpython/issues/95921]: Fix overly-broad source position information for chained comparisons used as branching conditions.

• gh-96821 [https://github.com/python/cpython/issues/96821]: Fix undefined behaviour in audioop.c.

• gh-96821 [https://github.com/python/cpython/issues/96821]: Fix undefined behaviour in _testcapimodule.c.

• gh-95778 [https://github.com/python/cpython/issues/95778]: When ValueError is raised if an integer is larger than the limit, mention the sys.set_int_max_str_digits() function in the error message. Patch by Victor Stinner.

• gh-96387 [https://github.com/python/cpython/issues/96387]: At Python exit, sometimes a thread holding the GIL can wait forever for a thread (usually a daemon thread) which requested to drop the GIL, whereas the thread already exited. To fix the race condition, the thread which requested the GIL drop now resets its request before exiting. Issue discovered and analyzed by Mingliang ZHAO. Patch by Victor Stinner.

• gh-96864 [https://github.com/python/cpython/issues/96864]: Fix a possible assertion failure, fatal error, or SystemError if a line tracing event raises an exception while opcode tracing is enabled.

• gh-95778 [https://github.com/python/cpython/issues/95778]: The PyLong_FromString function was refactored to make it more maintainable and extensible.

• gh-96678 [https://github.com/python/cpython/issues/96678]: Fix undefined behaviour in C code of null pointer arithmetic.

• gh-96754 [https://github.com/python/cpython/issues/96754]: Make sure that all frame objects created are created from valid interpreter frames. Prevents the possibility of invalid frames in backtraces and signal handlers.

• gh-90997 [https://github.com/python/cpython/issues/90997]: Improve the performance of reading and writing inline bytecode caches on some platforms.

• gh-96751 [https://github.com/python/cpython/issues/96751]: Remove dead code from CALL_FUNCTION_EX opcode.

• gh-90751 [https://github.com/python/cpython/issues/90751]: memoryview now supports half-floats. Patch by Donghee Na and Antoine Pitrou.

• gh-96678 [https://github.com/python/cpython/issues/96678]: Fix case of undefined behavior in ceval.c

• gh-64373 [https://github.com/python/cpython/issues/64373]: Convert _functools to argument clinic.

• gh-96641 [https://github.com/python/cpython/issues/96641]: Do not expose KeyWrapper in _functools.

• gh-96636 [https://github.com/python/cpython/issues/96636]: Ensure that tracing, sys.setrace(), is turned on immediately. In prerelease versions of 3.11, some tracing events might have been lost when turning on tracing in a __del__ method or interrupt.

• gh-96572 [https://github.com/python/cpython/issues/96572]: Fix use after free in trace refs build mode. Patch by Kumar Aditya.

• gh-96611 [https://github.com/python/cpython/issues/96611]: When loading a file with invalid UTF-8 inside a multiline string, a correct SyntaxError is emitted.

• gh-96612 [https://github.com/python/cpython/issues/96612]: Make sure that incomplete frames do not show up in tracemalloc traces.

• gh-90230 [https://github.com/python/cpython/issues/90230]: Fix compiler warnings and test failures when building with --enable-pystats.

• gh-96587 [https://github.com/python/cpython/issues/96587]: Correctly raise SyntaxError on exception groups ( PEP 654 [https://peps.python.org/pep-0654/]) on python versions prior to 3.11

• gh-96569 [https://github.com/python/cpython/issues/96569]: Remove two cases of undefined behavior, by adding NULL checks.

• gh-96582 [https://github.com/python/cpython/issues/96582]: Fix possible NULL pointer dereference in PyThreadCurrentFrames. Patch by Kumar Aditya.

• gh-91079 [https://github.com/python/cpython/issues/91079]: Separate Python recursion checking from C recursion checking which reduces the chance of C stack overflow and allows the recursion limit to be increased safely.

• gh-93911 [https://github.com/python/cpython/issues/93911]: Fix an issue that could prevent LOAD_ATTR from specializing properly when accessing properties.

• gh-96348 [https://github.com/python/cpython/issues/96348]: Emit a DeprecationWarning when throw(), throw() or athrow() are called with more than one argument.

• gh-95196 [https://github.com/python/cpython/issues/95196]: Disable incorrect pickling of the C implemented classmethod descriptors.

• gh-96364 [https://github.com/python/cpython/issues/96364]: Fix text signatures of list.__getitem__ and dict.__getitem__.

• gh-96352 [https://github.com/python/cpython/issues/96352]: Fix AttributeError missing name and obj attributes in object.__getattribute__(). Patch by Philip Georgi.

• gh-93554 [https://github.com/python/cpython/issues/93554]: Change the jump opcodes so that all conditional jumps are forward jumps. Backward jumps are converted by the assembler into a conditional forward jump whose target is the fallthrough block (and with a reversed condition), followed by an unconditional backward jump. For example:

POP_JUMP_IF_TRUE BACKWARD_TARGET becomes POP_JUMP_IF_FALSE NEXT_BLOCK; JUMP BACKWARD_TARGET.

All the directed conditional jump opcodes were removed: POP_JUMP_FORWARD_IF_TRUE, POP_JUMP_BACKWARD_IF_TRUE, POP_JUMP_FORWARD_IF_FALSE, POP_JUMP_BACKWARD_IF_FALSE, POP_JUMP_FORWARD_IF_NONE, POP_JUMP_BACKWARD_IF_NONE, POP_JUMP_FORWARD_IF_NOT_NONE, POP_JUMP_BACKWARD_IF_NOT_NONE.

The corresponding opcodes without direction are no longer pseudo-instructions, and they implement the forward conditional jumps.

• gh-96268 [https://github.com/python/cpython/issues/96268]: Loading a file with invalid UTF-8 will now report the broken character at the correct location.

• gh-96237 [https://github.com/python/cpython/issues/96237]: The internal field PyInterpreterFrame.ffunc is renamed to PyInterpreterFrame.ffuncobj and may be any object. The f_globals and f_builtin fields may hold junk values.

It is safest to treat the _PyInterpreterFrame struct as opaque.

• gh-96187 [https://github.com/python/cpython/issues/96187]: Fixed a bug that caused PyCodeGetExtra to return garbage for negative indexes. Patch by Pablo Galindo

• gh-96143 [https://github.com/python/cpython/issues/96143]: Add a new -X perf Python command line option as well as sys.activate_stack_trampoline() and sys.deactivate_stack_trampoline() function in the sys module that allows to set/unset the interpreter in a way that the Linux perf profiler can detect Python calls. The new sys.is_stack_trampoline_active() function allows to query the state of the perf trampoline. Design by Pablo Galindo. Patch by Pablo Galindo and Christian Heimes with contributions from Gregory P. Smith [Google] and Mark Shannon.

• gh-96071 [https://github.com/python/cpython/issues/96071]: Fix a deadlock in PyGILState_Ensure() when allocating new thread state. Patch by Kumar Aditya.

• gh-96046 [https://github.com/python/cpython/issues/96046]: PyType_Ready() now initializes ht_cached_keys and performs additional checks to ensure that type objects are properly configured. This avoids crashes in 3rd party packages that don't use regular API to create new types.

• gh-96005 [https://github.com/python/cpython/issues/96005]: On WASI ENOTCAPABLE is now mapped to PermissionError. The errno modules exposes the new error number. getpath.py now ignores PermissionError when it cannot open landmark files pybuilddir.txt and pyenv.cfg.

• gh-93678 [https://github.com/python/cpython/issues/93678]: Added test a harness for direct unit tests of the compiler's optimization stage. The testinternalcapi.optimizecfg() function runs the optimiser on a sequence of instructions. The CfgOptimizationTestCase class in test.support has utilities for invoking the optimizer and checking the output.

• gh-95245 [https://github.com/python/cpython/issues/95245]: Reduces the size of a "simple" Python object from 8 to 6 words by moving the weakreflist pointer into the preheader directly before the object's dict/values pointer.

• gh-90997 [https://github.com/python/cpython/issues/90997]: Compile virtual try/except blocks to handle exceptions raised during close() or throw() calls through a suspended frame.

• gh-95977 [https://github.com/python/cpython/issues/95977]: Optimized calling _get_() with vectorcall. Patch by Kumar Aditya.

• gh-91210 [https://github.com/python/cpython/issues/91210]: Improve error message when a parameter without a default value follows one with a default value, and show the same message, even when the non-default/default sequence is preceded by positional-only parameters.

• gh-95922 [https://github.com/python/cpython/issues/95922]: Fixed bug where the compiler's eliminate_empty_basic_blocks function ignores the last block of the code unit.

• gh-95818 [https://github.com/python/cpython/issues/95818]: Skip over incomplete frames in PyThreadState_GetFrame().

• gh-95876 [https://github.com/python/cpython/issues/95876]: Fix format string in PyPegenraise_error_known_location that can lead to memory corruption on some 64bit systems. The function was building a tuple with i (int) instead of n (Py_ssize_t) for Py_ssize_t arguments.

• gh-95605 [https://github.com/python/cpython/issues/95605]: Fix misleading contents of error message when converting an all-whitespace string to float.

• gh-95150 [https://github.com/python/cpython/issues/95150]: Update code object hashing and equality to consider all debugging and exception handling tables. This fixes an issue where certain non-identical code objects could be "deduplicated" during compilation.

• gh-91146 [https://github.com/python/cpython/issues/91146]: Reduce allocation size of list from str.split() and str.rsplit(). Patch by Donghee Na and Inada Naoki.

• gh-87092 [https://github.com/python/cpython/issues/87092]: Create a 'jump target label' abstraction in the compiler so that the compiler's codegen stage does not work directly with basic blocks. This prepares the code for changes to the underlying CFG generation mechanism.

• gh-95355 [https://github.com/python/cpython/issues/95355]: PyPegenParser_New now properly detects token memory allocation errors. Patch by Honglin Zhu.

• gh-90081 [https://github.com/python/cpython/issues/90081]: Run Python code in tracer/profiler function at full speed. Fixes slowdown in earlier versions of 3.11.

• gh-95324 [https://github.com/python/cpython/issues/95324]: Emit a warning in debug mode if an object does not call PyObject_GC_UnTrack() before deallocation. Patch by Pablo Galindo.

• gh-95245 [https://github.com/python/cpython/issues/95245]: Merge managed dict and values pointer into a single tagged pointer to save one word in the preheader.

• gh-93678 [https://github.com/python/cpython/issues/93678]: Add cfg_builder struct and refactor the relevant code so that a cfg can be constructed without an instance of the compiler struct.

• gh-95185 [https://github.com/python/cpython/issues/95185]: Prevented crashes in the AST constructor when compiling some absurdly long expressions like "+0"*1000000. RecursionError is now raised instead. Patch by Pablo Galindo

• gh-93351 [https://github.com/python/cpython/issues/93351]: ast.AST node positions are now validated when provided to compile() and other related functions. If invalid positions are detected, a ValueError will be raised.

• gh-94438 [https://github.com/python/cpython/issues/94438]: Fix an issue that caused extended opcode arguments and some conditional pops to be ignored when calculating valid jump targets for assignments to the f_lineno attribute of frame objects. In some cases, this could cause inconsistent internal state, resulting in a hard crash of the interpreter.

• gh-95060 [https://github.com/python/cpython/issues/95060]: Undocumented PyCode_Addr2Location function now properly returns when addrq argument is less than zero.

• gh-95113 [https://github.com/python/cpython/issues/95113]: Replace all EXTENDED_ARG_QUICK instructions with basic EXTENDED_ARG instructions in unquickened code. Consumers of non-adaptive bytecode should be able to handle extended arguments the same way they were handled in CPython 3.10 and older.

• gh-91409 [https://github.com/python/cpython/issues/91409]: Fix incorrect source location info caused by certain optimizations in the bytecode compiler.

• gh-95023 [https://github.com/python/cpython/issues/95023]: Implement os.setns() and os.unshare() for Linux. Patch by Noam Cohen.

• gh-94036 [https://github.com/python/cpython/issues/94036]: Fix incorrect source location info for some multiline attribute accesses and method calls.

• gh-94938 [https://github.com/python/cpython/issues/94938]: Fix error detection in some builtin functions when keyword argument name is an instance of a str subclass with overloaded __eq__ and __hash__. Previously it could cause SystemError or other undesired behavior.

• gh-94996 [https://github.com/python/cpython/issues/94996]: ast.parse() will no longer parse function definitions with positional-only params when passed feature_version less than (3, 8). Patch by Shantanu Jain.

• gh-94739 [https://github.com/python/cpython/issues/94739]: Allow jumping within, out of, and across exception handlers in the debugger.

• gh-94949 [https://github.com/python/cpython/issues/94949]: ast.parse() will no longer parse parenthesized context managers when passed feature_version less than (3, 9). Patch by Shantanu Jain.

• gh-94947 [https://github.com/python/cpython/issues/94947]: ast.parse() will no longer parse assignment expressions when passed feature_version less than (3, 8). Patch by Shantanu Jain.

• gh-91256 [https://github.com/python/cpython/issues/91256]: Ensures the program name is known for help text during interpreter startup.

• gh-94869 [https://github.com/python/cpython/issues/94869]: Fix the column offsets for some expressions in multiline fstrings ast nodes. Patch by Pablo Galindo.

• gh-94893 [https://github.com/python/cpython/issues/94893]: Fix an issue where frame object manipulations could corrupt inline bytecode caches.

• gh-94822 [https://github.com/python/cpython/issues/94822]: Fix an issue where lookups of metaclass descriptors may be ignored when an identically-named attribute also exists on the class itself.

• gh-91153 [https://github.com/python/cpython/issues/91153]: Fix an issue where a bytearray item assignment could crash if it's resized by the new value's __index__() method.

• gh-90699 [https://github.com/python/cpython/issues/90699]: Fix reference counting bug in bool._repr_(). Patch by Kumar Aditya.

• gh-94694 [https://github.com/python/cpython/issues/94694]: Fix an issue that could cause code with multiline method lookups to have misleading or incorrect column offset information. In some cases (when compiling a hand-built AST) this could have resulted in a hard crash of the interpreter.

• gh-93252 [https://github.com/python/cpython/issues/93252]: Fix an issue that caused internal frames to outlive failed Python function calls, possibly resulting in memory leaks or hard interpreter crashes.

• gh-94215 [https://github.com/python/cpython/issues/94215]: Fix an issue where exceptions raised by line-tracing events would cause frames to be left in an invalid state, possibly resulting in a hard crash of the interpreter.

• gh-92228 [https://github.com/python/cpython/issues/92228]: Disable the compiler's inline-small-exit-blocks optimization for exit blocks that are associated with source code lines. This fixes a bug where the debugger cannot tell where an exception handler ends and the following code block begins.

• gh-94485 [https://github.com/python/cpython/issues/94485]: Line number of a module's RESUME instruction is set to 0 as specified in PEP 626 [https://peps.python.org/pep-0626/].

• gh-94438 [https://github.com/python/cpython/issues/94438]: Account for instructions that can push NULL to the stack when setting line number in a frame. Prevents some (unlikely) crashes.

• gh-91719 [https://github.com/python/cpython/issues/91719]: Reload opcode when raising unknown opcode error in the interpreter main loop, for C compilers to generate dispatching code independently.

• gh-94329 [https://github.com/python/cpython/issues/94329]: Compile and run code with unpacking of extremely large sequences (1000s of elements). Such code failed to compile. It now compiles and runs correctly.

• gh-94360 [https://github.com/python/cpython/issues/94360]: Fixed a tokenizer crash when reading encoded files with syntax errors from stdin with non utf-8 encoded text. Patch by Pablo Galindo

• gh-88116 [https://github.com/python/cpython/issues/88116]: Fix an issue when reading line numbers from code objects if the encoded line numbers are close to INT_MIN. Patch by Pablo Galindo

• gh-94262 [https://github.com/python/cpython/issues/94262]: Don't create frame objects for incomplete frames. Prevents the creation of generators and closures from being observable to Python and C extensions, restoring the behavior of 3.10 and earlier.

• gh-94192 [https://github.com/python/cpython/issues/94192]: Fix error for dictionary literals with invalid expression as value.

• gh-87995 [https://github.com/python/cpython/issues/87995]: types.MappingProxyType instances are now hashable if the underlying mapping is hashable.

• gh-93883 [https://github.com/python/cpython/issues/93883]: Revise the display strategy of traceback enhanced error locations. The indicators are only shown when the location doesn't span the whole line.

• gh-94163 [https://github.com/python/cpython/issues/94163]: Add BINARY_SLICE and STORE_SLICE instructions for more efficient handling and better specialization of slicing operations, where the slice is explicit in the source code.

• gh-94021 [https://github.com/python/cpython/issues/94021]: Fix unreachable code warning in Python/specialize.c.

• gh-93911 [https://github.com/python/cpython/issues/93911]: Specialize LOAD_ATTR for objects with custom __getattribute__.

• gh-93955 [https://github.com/python/cpython/issues/93955]: Improve performance of attribute lookups on objects with custom __getattribute__ and __getattr__. Patch by Ken Jin.

• gh-93911 [https://github.com/python/cpython/issues/93911]: Specialize LOAD_ATTR for property() attributes.

• gh-93678 [https://github.com/python/cpython/issues/93678]: Refactor compiler optimisation code so that it no longer needs the struct assembler and struct compiler passed around. Instead, each function takes the CFG and other data that it actually needs. This will make it possible to test this code directly.

• gh-93841 [https://github.com/python/cpython/issues/93841]: When built with -enable-pystats, sys._stats_on(), sys._stats_off(), sys._stats_clear() and sys._stats_dump() functions have been added to enable gathering stats for parts of programs.

• gh-93516 [https://github.com/python/cpython/issues/93516]: Store offset of first traceable instruction in code object to avoid having to recompute it for each instruction when tracing.

• gh-93516 [https://github.com/python/cpython/issues/93516]: Lazily create a table mapping bytecode offsets to line numbers to speed up calculation of line numbers when tracing.

• gh-89828 [https://github.com/python/cpython/issues/89828]: types.GenericAlias no longer relays the __class__ attribute. For example, isinstance(list[int], type) no longer returns True.

• gh-93678 [https://github.com/python/cpython/issues/93678]: Refactor the compiler to reduce boilerplate and repetition.

• gh-93671 [https://github.com/python/cpython/issues/93671]: Fix some exponential backtrace case happening with deeply nested sequence patterns in match statements. Patch by Pablo Galindo

• gh-93662 [https://github.com/python/cpython/issues/93662]: Make sure that the end column offsets are correct in multiline method calls. Previously, the end column could precede the column offset.

• gh-93461 [https://github.com/python/cpython/issues/93461]: importlib.invalidate_caches() now drops entries from sys.path_importer_cache with a relative path as name. This solves a caching issue when a process changes its current working directory.

FileFinder no longer inserts a dot in the path, e.g. egg./spam is now eggspam.

• gh-93621 [https://github.com/python/cpython/issues/93621]: Change order of bytecode instructions emitted for with and async with to reduce the number of entries in the exception table.

• gh-93533 [https://github.com/python/cpython/issues/93533]: Reduce the size of the inline cache for LOAD_METHOD by 2 bytes.

• gh-93444 [https://github.com/python/cpython/issues/93444]: Removed redundant fields from the compiler's basicblock struct: b_nofallthrough, b_exit, b_return. They can be easily calculated from the opcode of the last instruction of the block.

• gh-93429 [https://github.com/python/cpython/issues/93429]: LOAD_METHOD instruction has been removed. It was merged back into LOAD_ATTR.

• gh-93418 [https://github.com/python/cpython/issues/93418]: Fixed an assert where an fstring has an equal sign '=' following an expression, but there's no trailing brace. For example, f"{i=".

• gh-93382 [https://github.com/python/cpython/issues/93382]: Cache the result of PyCode_GetCode() function to restore the O(1) lookup of the co_code attribute.

• gh-93359 [https://github.com/python/cpython/issues/93359]: Ensure that custom ast nodes without explicit end positions can be compiled. Patch by Pablo Galindo.

• gh-93356 [https://github.com/python/cpython/issues/93356]: Code for exception handlers is emitted at the end of the code unit's bytecode. This avoids one jump when no exception is raised.

• gh-93354 [https://github.com/python/cpython/issues/93354]: Use exponential backoff for specialization counters in the interpreter. Can reduce the number of failed specializations significantly and avoid slowdown for those parts of a program that are not suitable for specialization.

• gh-93283 [https://github.com/python/cpython/issues/93283]: Improve error message for invalid syntax of conversion character in fstring expressions.

• gh-93345 [https://github.com/python/cpython/issues/93345]: Fix a crash in substitution of a TypeVar in nested generic alias after TypeVarTuple.

• gh-93223 [https://github.com/python/cpython/issues/93223]: When a bytecode instruction jumps to an unconditional jump instruction, the first instruction can often be optimized to target the unconditional jump's target directly. For tracing reasons, this would previously only occur if both instructions have the same line number. This also now occurs if the unconditional jump is artificial, i.e., if it has no associated line number.

• gh-84694 [https://github.com/python/cpython/issues/84694]: The --experimental-isolated-subinterpreters configure option and EXPERIMENTAL_ISOLATED_SUBINTERPRETERS macro have been removed.

• gh-91924 [https://github.com/python/cpython/issues/91924]: Fix __lltrace__ debug feature if the stdout encoding is not UTF-8. Patch by Victor Stinner.

• gh-93040 [https://github.com/python/cpython/issues/93040]: Wraps unused parameters in Objects/obmalloc.c with Py_UNUSED.

• gh-93143 [https://github.com/python/cpython/issues/93143]: Avoid NULL checks for uninitialized local variables by determining at compile time which variables must be initialized.

• gh-93061 [https://github.com/python/cpython/issues/93061]: Backward jumps after async for loops are no longer given dubious line numbers.

• gh-93065 [https://github.com/python/cpython/issues/93065]: Fix contextvars HAMT implementation to handle iteration over deep trees.

The bug was discovered and fixed by Eli Libman. See MagicStack/immutables#84 [https://github.com/MagicStack/immutables/issues/84] for more details.

• gh-93012 [https://github.com/python/cpython/issues/93012]: Added the new function PyType_FromMetaclass(), which generalizes the existing PyType_FromModuleAndSpec() using an additional metaclass argument. This is useful for language binding tools, where it can be used to intercept type-related operations like subclassing or static attribute access by specifying a metaclass with custom slots.

Importantly, PyType_FromMetaclass() is available in the Limited API, which provides a path towards migrating more binding tools onto the Stable ABI.

• gh-93021 [https://github.com/python/cpython/issues/93021]: Fix the __textsignature_ for _get_() methods implemented in C. Patch by Jelle Zijlstra.

• gh-89914 [https://github.com/python/cpython/issues/89914]: The operand of the YIELD_VALUE instruction is set to the stack depth. This is done to help frame handling on yield and may assist debuggers.

• gh-92955 [https://github.com/python/cpython/issues/92955]: Fix memory leak in code object's lines and positions iterators as they were not finalized at exit. Patch by Kumar Aditya.

• gh-92930 [https://github.com/python/cpython/issues/92930]: Fixed a crash in _pickle.c from mutating collections during __reduce__ or persistent_id.

• gh-90690 [https://github.com/python/cpython/issues/90690]: The PRECALL instruction has been removed. It offered only a small advantage for specialization and is not needed in the vast majority of cases.

• gh-92914 [https://github.com/python/cpython/issues/92914]: Always round the allocated size for lists up to the nearest even number.

• gh-92858 [https://github.com/python/cpython/issues/92858]: Improve error message for some suites with syntax error before ':'

• gh-90473 [https://github.com/python/cpython/issues/90473]: Decrease default recursion limit on WASI to address limited call stack size.

• gh-92804 [https://github.com/python/cpython/issues/92804]: Fix memory leak in memoryview iterator as it was not finalized at exit. Patch by Kumar Aditya.

• gh-92777 [https://github.com/python/cpython/issues/92777]: Specialize LOAD_METHOD for objects with lazy dictionaries. Patch by Ken Jin.

• gh-92658 [https://github.com/python/cpython/issues/92658]: Add support for connecting and binding to Hyper-V sockets on Windows Hyper-V hosts and guests.

• gh-92236 [https://github.com/python/cpython/issues/92236]: Remove spurious "LINE" event when starting a generator or coroutine, visible tracing functions implemented in C.

• gh-91102 [https://github.com/python/cpython/issues/91102]: warnings.warnexplicit() is ported to Argument Clinic.

• gh-92619 [https://github.com/python/cpython/issues/92619]: Make the compiler duplicate an exit block only if none of its instructions have a lineno (previously only the first instruction in the block was checked, leading to unnecessarily duplicated blocks).

• gh-88750 [https://github.com/python/cpython/issues/88750]: The deprecated debug build only PYTHONTHREADDEBUG environment variable no longer does anything.

• gh-92261 [https://github.com/python/cpython/issues/92261]: Fix hang when trying to iterate over a typing.Union.

• gh-91432 [https://github.com/python/cpython/issues/91432]: Specialized the FOR_ITER opcode using the PEP 659 machinery

• gh-91399 [https://github.com/python/cpython/issues/91399]: Removed duplicate '{0, 0, 0, 0, 0, 0}' entry in 'Objects/unicodetype_db.h'.

• gh-91578 [https://github.com/python/cpython/issues/91578]: Updates the error message for abstract class.

• bpo-47091 [https://bugs.python.org/issue?@action=redirect&bpo=47091]: Improve performance of repetition of list and tuple by using memcpy to copy data and performing the reference increments in one step.

• bpo-46142 [https://bugs.python.org/issue?@action=redirect&bpo=46142]: Make --help output shorter by moving some info to the new --help-env and --help-xoptions commandline options. Also add --help-all option to print complete usage.

• bpo-42316 [https://bugs.python.org/issue?@action=redirect&bpo=42316]: Document some places where an assignment expression needs parentheses.

库

• gh-89237 [https://github.com/python/cpython/issues/89237]: Fix hang on Windows in subprocess.wait_closed() in asyncio with ProactorEventLoop. Patch by Kumar Aditya.

• gh-97928 [https://github.com/python/cpython/issues/97928]: tkinter.Text.count() raises now an exception for options starting with "-" instead of silently ignoring them.

• gh-98393 [https://github.com/python/cpython/issues/98393]: The os module no longer accepts bytes-like paths, like bytearray and memoryview types: only the exact bytes type is accepted for bytes strings. Patch by Victor Stinner.

• gh-98363 [https://github.com/python/cpython/issues/98363]: Added itertools.batched() to batch data into lists of a given length with the last list possibly being shorter than the others.

• gh-98331 [https://github.com/python/cpython/issues/98331]: Update the bundled copies of pip and setuptools to versions 22.3 and 65.5.0 respectively.

• gh-98307 [https://github.com/python/cpython/issues/98307]: A createSocket() method was added to SysLogHandler.

• gh-96035 [https://github.com/python/cpython/issues/96035]: Fix bug in urllib.parse.urlparse() that causes certain port numbers containing whitespace, underscores, plus and minus signs, or nonASCII digits to be incorrectly accepted.

• gh-98257 [https://github.com/python/cpython/issues/98257]: Make sys.setprofile() and sys.settrace() functions reentrant. They can no long fail with: RuntimeError("Cannot install a trace function while another trace function is being installed"). Patch by Victor Stinner.

• gh-98251 [https://github.com/python/cpython/issues/98251]: Allow venv to pass along PYTHON* variables to ensurepip and pip when they do not impact path resolution

• gh-94597 [https://github.com/python/cpython/issues/94597]: Deprecated asyncio.AbstractEventLoopPolicy.get_child_watcher() and asyncio.AbstractEventLoopPolicy.set_child_watcher() methods to be removed in Python 3.14. Patch by Kumar Aditya.

• gh-98178 [https://github.com/python/cpython/issues/98178]: On macOS, fix a crash in syslog.syslog() in multithreaded applications. On macOS, the libc syslog() function is not threadsafe, so syslog.syslog() no longer releases the GIL to call it. Patch by Victor Stinner.

• gh-44098 [https://github.com/python/cpython/issues/44098]: Release the GIL when creating mmap.mmap objects on Unix.

• gh-87730 [https://github.com/python/cpython/issues/87730]: Wrap network errors consistently in urllib FTP support, so the test suite doesn't fail when a network is available but the public internet is not reachable.

• gh-94597 [https://github.com/python/cpython/issues/94597]: The child watcher classes MultiLoopChildWatcher, FastChildWatcher and SafeChildWatcher are deprecated and will be removed in Python 3.14. Patch by Kumar Aditya.

• gh-98023 [https://github.com/python/cpython/issues/98023]: Change default child watcher to PidfdChildWatcher on Linux systems which supports it. Patch by Kumar Aditya.

• gh-90985 [https://github.com/python/cpython/issues/90985]: Earlier in 3.11 we deprecated asyncio.Task.cancel("message"). We realized we were too harsh, and have undeprecated it.

• gh-65961 [https://github.com/python/cpython/issues/65961]: Do not rely solely on __cached__ on modules; code will also support __spec__.cached.

• gh-97646 [https://github.com/python/cpython/issues/97646]: Replace deprecated application/javascript with text/javascript in mimetypes. See RFC 9239 [https://datatracker.ietf.org/doc/html/rfc9239.html]. Patch by Noam Cohen.

• gh-97930 [https://github.com/python/cpython/issues/97930]: Apply changes from importlib_resources 5.8 and 5.9: Traversable.joinpath provides a concrete implementation. as_file now supports directories of resources.

• gh-97850 [https://github.com/python/cpython/issues/97850]: Remove deprecated importlib.util.set_loader() and importlib.util.module_for_loader() from importlib.util.

• gh-97837 [https://github.com/python/cpython/issues/97837]: Change deprecate warning message in unittest from It is deprecated to return a value!=None

to

It is deprecated to return a value that is not None from a test case

• gh-97825 [https://github.com/python/cpython/issues/97825]: Fixes AttributeError when subprocess.check_output() is used with argument input=None and either of the arguments encoding or errors are used.

• gh-97008 [https://github.com/python/cpython/issues/97008]: NameError and AttributeError spelling suggestions provided since gh-82711 [https://github.com/python/cpython/issues/82711] are now also emitted by the pure Python traceback module. Tests for those suggestions now exercise both implementations to ensure they are equivalent. Patch by Carl Friedrich Bolz-Tereick and Łukasz Langa.

• gh-97799 [https://github.com/python/cpython/issues/97799]: dataclass now uses inspect.get_annotations() to examine the annotations on class objects.

• gh-97781 [https://github.com/python/cpython/issues/97781]: Removed deprecated interfaces in importlib.metadata (entry points accessed as dictionary, implicit dictionary construction of sequence of EntryPoint objects, mutablility of EntryPoints result, access of entry point by index). entry_points now has a simpler, more straightforward API (returning EntryPoints).

• gh-96827 [https://github.com/python/cpython/issues/96827]: Avoid spurious tracebacks from asyncio when default executor cleanup is delayed until after the event loop is closed (e.g. as the result of a keyboard interrupt).

• gh-95534 [https://github.com/python/cpython/issues/95534]: gzip.GzipFile.read() reads 10% faster.

• gh-97592 [https://github.com/python/cpython/issues/97592]: Avoid a crash in the C version of asyncio.Future.remove_done_callback() when an evil argument is passed.

• gh-97639 [https://github.com/python/cpython/issues/97639]: Remove tokenize.NL check from tabnanny.

• gh-97545 [https://github.com/python/cpython/issues/97545]: Make Semaphore run faster.

• gh-73588 [https://github.com/python/cpython/issues/73588]: Fix generation of the default name of tkinter.Checkbutton. Previously, checkbuttons in different parent widgets could have the same short name and share the same state if arguments "name" and "variable" are not specified. Now they are globally unique.

• gh-96865 [https://github.com/python/cpython/issues/96865]: fix Flag to use boundary CONFORM

This restores previous Flag behavior of allowing flags with non-sequential values to be combined; e.g.

class Skip(Flag): TWO = 2 EIGHT = 8

Skip.TWO | Skip.EIGHT ->

• gh-97005 [https://github.com/python/cpython/issues/97005]: Update bundled libexpat to 2.4.9

• gh-85760 [https://github.com/python/cpython/issues/85760]: Fix race condition in asyncio where process_exited() called before the pipe_data_received() leading to inconsistent output. Patch by Kumar Aditya.

• gh-96704 [https://github.com/python/cpython/issues/96704]: Pass the correct contextvars.Context when a asyncio exception handler is called on behalf of a task or callback handle. This adds a new Task method, get_context, and also a new Handle method with the same name. If this method is not found on a task object (perhaps because it is a third-party library that does not yet provide this method), the context prevailing at the time the exception handler is called is used.

• gh-96819 [https://github.com/python/cpython/issues/96819]: Fixed check in multiprocessing.resource_tracker that guarantees that the length of a write to a pipe is not greater than PIPE_BUF.

• gh-95865 [https://github.com/python/cpython/issues/95865]: Reduce urllib.parse.quote_from_bytes() memory use on large values.

Contributed by Dennis Sweeney.

• gh-96741 [https://github.com/python/cpython/issues/96741]: Corrected type annotation for dataclass attribute pstats.FunctionProfile.ncalls to be str.

• gh-96734 [https://github.com/python/cpython/issues/96734]: Update unicodedata database to Unicode 15.0.0.

• gh-96735 [https://github.com/python/cpython/issues/96735]: Fix undefined behaviour in struct.unpack().

• gh-46412 [https://github.com/python/cpython/issues/46412]: Improve performance of bool(db) for large ndb/gdb databases. Previously this would call len(db) which would iterate over all keys — the answer (empty or not) is known after the first key.

• gh-96652 [https://github.com/python/cpython/issues/96652]: Fix the faulthandler implementation of faulthandler.register(signal, chain=True) if the sigaction() function is not available: don't call the previous signal handler if it's NULL. Patch by Victor Stinner.

• gh-68163 [https://github.com/python/cpython/issues/68163]: Correct conversion of numbers.Rational's to float.

• gh-96538 [https://github.com/python/cpython/issues/96538]: Speed up bisect.bisect() functions by taking advantage of type-stability.

• gh-96465 [https://github.com/python/cpython/issues/96465]: Fraction hashes are now cached.

• gh-96079 [https://github.com/python/cpython/issues/96079]: In typing, fix missing field name and incorrect __module__ in _AnnotatedAlias.

• gh-96415 [https://github.com/python/cpython/issues/96415]: Remove types._cell_factory from module namespace.

• gh-95987 [https://github.com/python/cpython/issues/95987]: Fix repr of Any subclasses.

• gh-96388 [https://github.com/python/cpython/issues/96388]: Work around missing socket functions in socket's _repr_.

• gh-96385 [https://github.com/python/cpython/issues/96385]: Fix TypeVarTuple.__typing_prepare_subst__. TypeError was not raised when using more than one TypeVarTuple, like [*T, *V] in type alias substitutions.

• gh-96142 [https://github.com/python/cpython/issues/96142]: Add match_args, kw_only, slots, and weakref_slot to _DataclassParams.

• gh-96073 [https://github.com/python/cpython/issues/96073]: In inspect, fix overeager replacement of "typing." in formatting annotations.

• gh-89258 [https://github.com/python/cpython/issues/89258]: Added a getChildren() method to logging.Logger, to get the immediate child loggers of a logger.

• gh-96346 [https://github.com/python/cpython/issues/96346]: Use double caching for compiled RE patterns.

• gh-96349 [https://github.com/python/cpython/issues/96349]: Fixed a minor performance regression in threading.Event.__init__()

• gh-90467 [https://github.com/python/cpython/issues/90467]: Fix asyncio.streams.StreamReaderProtocol to keep a strong reference to the created task, so that it's not garbage collected

• gh-96172 [https://github.com/python/cpython/issues/96172]: Fix a bug in unicodedata: east_asian_width used to return the wrong value for unassigned characters; and for yet unassigned, but reserved characters.

• gh-96159 [https://github.com/python/cpython/issues/96159]: Fix a performance regression in logging TimedRotatingFileHandler. Only check for special files when the rollover time has passed.

• gh-96175 [https://github.com/python/cpython/issues/96175]: Fix unused localName parameter in the Attr class in xml.dom.minidom.

• gh-96145 [https://github.com/python/cpython/issues/96145]: Add AttrDict to JSON module for use with object_hook.

• gh-96052 [https://github.com/python/cpython/issues/96052]: Fix handling compiler warnings (SyntaxWarning and DeprecationWarning) in codeop.compile_command() when checking for incomplete input. Previously it emitted warnings and raised a SyntaxError. Now it always returns None for incomplete input without emitting any warnings.

• gh-96125 [https://github.com/python/cpython/issues/96125]: Fix incorrect condition that causes sys.thread_info.name to be wrong on pthread platforms.

• gh-96019 [https://github.com/python/cpython/issues/96019]: Fix a bug in the makeunicodedata.py script leading to about 13 KiB of space saving in the unicodedata module, specifically the character decomposition data.

• gh-95463 [https://github.com/python/cpython/issues/95463]: Remove an incompatible change from bpo-28080 [https://bugs.python.org/issue?@action=redirect&bpo=28080] that caused a regression that ignored the utf8 in ZipInfo.flag_bits. Patch by Pablo Galindo.

• gh-69142 [https://github.com/python/cpython/issues/69142]: Add %:z strftime format code (generates tzoffset with colons as separator), see strftime() 和 strptime() 的行为.

• gh-95899 [https://github.com/python/cpython/issues/95899]: Fix asyncio.Runner to call asyncio.set_event_loop() only once to avoid calling attach_loop() multiple times on child watchers. Patch by Kumar Aditya.

• gh-95736 [https://github.com/python/cpython/issues/95736]: Fix unittest.IsolatedAsyncioTestCase to set event loop before calling setup functions. Patch by Kumar Aditya.

• gh-95865 [https://github.com/python/cpython/issues/95865]: Speed up urllib.parse.quote_from_bytes() by replacing a list comprehension with map().

• gh-95861 [https://github.com/python/cpython/issues/95861]: Add support for computing Spearman's correlation coefficient to the existing statistics.correlation() function.

• gh-95804 [https://github.com/python/cpython/issues/95804]: Fix logging shutdown handler so it respects MemoryHandler.flushOnClose.

• gh-95704 [https://github.com/python/cpython/issues/95704]: When a task catches asyncio.CancelledError and raises some other error, the other error should generally not silently be suppressed.

• gh-95149 [https://github.com/python/cpython/issues/95149]: The HTTPStatus enum offers a couple of properties to indicate the HTTP status category e.g. HTTPStatus.OK.is_success.

• gh-95609 [https://github.com/python/cpython/issues/95609]: Update bundled pip to 22.2.2.

• gh-95289 [https://github.com/python/cpython/issues/95289]: Fix asyncio.TaskGroup to propagate exception when asyncio.CancelledError was replaced with another exception by a context manager. Patch by Kumar Aditya and Guido van Rossum.

• gh-94909 [https://github.com/python/cpython/issues/94909]: Fix incorrect joining of relative Windows paths with drives in pathlib.PurePath initializer.

• gh-95385 [https://github.com/python/cpython/issues/95385]: Faster json.dumps() when sorting of keys is not requested (default).

• gh-83901 [https://github.com/python/cpython/issues/83901]: Improve Signature.bind error message for missing keyword-only arguments.

• gh-95339 [https://github.com/python/cpython/issues/95339]: Update bundled pip to 22.2.1.

• gh-95045 [https://github.com/python/cpython/issues/95045]: Fix GC crash when deallocating _lsprof.Profiler by untracking it before calling any callbacks. Patch by Kumar Aditya.

• gh-95231 [https://github.com/python/cpython/issues/95231]: Fail gracefully if EPERM or ENOSYS is raised when loading crypt methods. This may happen when trying to load MD5 on a Linux kernel with FIPS enabled.

• gh-95097 [https://github.com/python/cpython/issues/95097]: Fix asyncio.run() for asyncio.Task implementations without uncancel() method. Patch by Kumar Aditya.

• gh-95087 [https://github.com/python/cpython/issues/95087]: Fix IndexError in parsing invalid date in the email module.

• gh-95199 [https://github.com/python/cpython/issues/95199]: Upgrade bundled setuptools to 63.2.0.

• gh-95194 [https://github.com/python/cpython/issues/95194]: Upgrade bundled pip to 22.2.

• gh-93899 [https://github.com/python/cpython/issues/93899]: Fix check for existence of os.EFD_CLOEXEC, os.EFD_NONBLOCK and os.EFD_SEMAPHORE flags on older kernel versions where these flags are not present. Patch by Kumar Aditya.

• gh-95166 [https://github.com/python/cpython/issues/95166]: Fix concurrent.futures.Executor.map() to cancel the currently waiting on future on an error - e.g. TimeoutError or KeyboardInterrupt.

• gh-95132 [https://github.com/python/cpython/issues/95132]: Fix a sqlite3 regression where *args and **kwds were incorrectly relayed from connect() to the Connection factory. The regression was introduced in 3.11a1 with PR 24421 (gh-85128 [https://github.com/python/cpython/issues/85128]). Patch by Erlend E. Aasland.

• gh-93157 [https://github.com/python/cpython/issues/93157]: Fix fileinput module didn't support errors option when inplace is true.

• gh-91212 [https://github.com/python/cpython/issues/91212]: Fixed flickering of the turtle window when the tracer is turned off. Patch by Shin-myoung-serp.

• gh-95077 [https://github.com/python/cpython/issues/95077]: Add deprecation warning for enum member.member access (e.g. Color.RED.BLUE). Remove EnumMeta.__getattr__.

• gh-95109 [https://github.com/python/cpython/issues/95109]: Ensure that timeouts scheduled with asyncio.Timeout that have already expired are delivered promptly.

• gh-95105 [https://github.com/python/cpython/issues/95105]: wsgiref.types.InputStream.__iter__() should return Iterator[bytes], not Iterable[bytes]. Patch by Shantanu Jain.

• gh-95066 [https://github.com/python/cpython/issues/95066]: Replaced assert with exception in ast.parse(), when feature_version has an invalid major version. Patch by Shantanu Jain.

• gh-77617 [https://github.com/python/cpython/issues/77617]: Add sqlite3 commandline interface. Patch by Erlend Aasland.

• gh-95005 [https://github.com/python/cpython/issues/95005]: Replace _PyAccu with _PyUnicodeWriter in JSON encoder and StringIO and remove the _PyAccu implementation.

• gh-90085 [https://github.com/python/cpython/issues/90085]: Remove -c/--clock and -t/--time CLI options of timeit. The options had been deprecated since Python 3.3 and the functionality was removed in Python 3.7. Patch by Shantanu Jain.

• gh-94857 [https://github.com/python/cpython/issues/94857]: Fix refleak in _io.TextIOWrapper.reconfigure. Patch by Kumar Aditya.

• gh-94821 [https://github.com/python/cpython/issues/94821]: Fix binding of unix socket to empty address on Linux to use an available address from the abstract namespace, instead of "0".

• gh-94736 [https://github.com/python/cpython/issues/94736]: Fix crash when deallocating an instance of a subclass of _multiprocessing.SemLock. Patch by Kumar Aditya.

• gh-81620 [https://github.com/python/cpython/issues/81620]: Add random.binomialvariate().

• gh-74116 [https://github.com/python/cpython/issues/74116]: Allow asyncio.StreamWriter.drain() to be awaited concurrently by multiple tasks. Patch by Kumar Aditya.

• gh-87822 [https://github.com/python/cpython/issues/87822]: When called with capture_locals=True, the traceback module functions swallow exceptions raised from calls to repr() on local variables of frames. This is in order to prioritize the original exception over rendering errors. An indication of the failure is printed in place of the missing value. (Patch by Simon-Martin Schroeder).

• gh-88050 [https://github.com/python/cpython/issues/88050]: Fix asyncio subprocess transport to kill process cleanly when process is blocked and avoid RuntimeError when loop is closed. Patch by Kumar Aditya.

• gh-94637 [https://github.com/python/cpython/issues/94637]: SSLContext.set_default_verify_paths() now releases the GIL around SSL_CTXsetdefault_verify_paths call. The function call performs I/O and CPU intensive work.

• gh-94309 [https://github.com/python/cpython/issues/94309]: Deprecate aliases typing.Hashable and typing.Sized

• gh-92546 [https://github.com/python/cpython/issues/92546]: An undocumented python -m pprint benchmark is moved into pprint suite of pyperformance. Patch by Oleg Iarygin.

• gh-94607 [https://github.com/python/cpython/issues/94607]: Fix subclassing complex generics with type variables in typing. Previously an error message saying Some type variables … are not listed in Generic[…] was shown. typing no longer populates __parameters__ with the __parameters__ of a Python class.

• gh-94619 [https://github.com/python/cpython/issues/94619]: Remove the long-deprecated module_repr() from importlib.

• gh-93910 [https://github.com/python/cpython/issues/93910]: The ability to access the other values of an enum on an enum (e.g. Color.RED.BLUE) has been restored in order to fix a performance regression.

• gh-93896 [https://github.com/python/cpython/issues/93896]: Fix asyncio.run() and unittest.IsolatedAsyncioTestCase to always the set event loop as it was done in Python 3.10 and earlier. Patch by Kumar Aditya.

• gh-94343 [https://github.com/python/cpython/issues/94343]: Allow setting the attributes of reprlib.Repr during object initialization

• gh-94382 [https://github.com/python/cpython/issues/94382]: Port static types of _multiprocessing module to heap types. Patch by Kumar Aditya.

• gh-78724 [https://github.com/python/cpython/issues/78724]: Fix crash in struct.Struct when it was not completely initialized by initializing it in _new_(). Patch by Kumar Aditya.

• gh-94510 [https://github.com/python/cpython/issues/94510]: Reentrant calls to sys.setprofile() and sys.settrace() now raise RuntimeError. Patch by Pablo Galindo.

• gh-92336 [https://github.com/python/cpython/issues/92336]: Fix bug where linecache.getline() fails on bad files with UnicodeDecodeError or SyntaxError. It now returns an empty string as per the documentation.

• gh-94398 [https://github.com/python/cpython/issues/94398]: Once a asyncio.TaskGroup has started shutting down (i.e., at least one task has failed and the task group has started cancelling the remaining tasks), it should not be possible to add new tasks to the task group.

• gh-94383 [https://github.com/python/cpython/issues/94383]: xml.etree: Remove the ElementTree.Element.copy() method of the pure Python implementation, deprecated in Python 3.10, use the copy.copy() function instead. The C implementation of xml.etree has no copy() method, only a _copy_() method. Patch by Victor Stinner.

• gh-94379 [https://github.com/python/cpython/issues/94379]: zipimport: Remove find_loader() and find_module() methods, deprecated in Python 3.10: use the find_spec() method instead. See PEP 451 [https://peps.python.org/pep-0451/] for the rationale. Patch by Victor Stinner.

• gh-94352 [https://github.com/python/cpython/issues/94352]: shlex.split(): Passing None for s argument now raises an exception, rather than reading sys.stdin. The feature was deprecated in Python 3.9. Patch by Victor Stinner.

• gh-94318 [https://github.com/python/cpython/issues/94318]: Strip trailing spaces in pydoc text output.

• gh-89988 [https://github.com/python/cpython/issues/89988]: Fix memory leak in pickle.Pickler when looking up dispatch_table. Patch by Kumar Aditya.

• gh-90016 [https://github.com/python/cpython/issues/90016]: Deprecate sqlite3 default adapters and converters. Patch by Erlend E. Aasland.

• gh-94254 [https://github.com/python/cpython/issues/94254]: Fixed types of struct module to be immutable. Patch by Kumar Aditya.

• gh-93259 [https://github.com/python/cpython/issues/93259]: Now raise ValueError when None or an empty string are passed to Distribution.from_name (and other callers).

• gh-74696 [https://github.com/python/cpython/issues/74696]: shutil.make_archive() now passes the root_dir argument to custom archivers which support it.

• gh-94216 [https://github.com/python/cpython/issues/94216]: The dis module now has the opcodes for pseudo instructions (those which are used by the compiler during code generation but then removed or replaced by real opcodes before the final bytecode is emitted).

• gh-93096 [https://github.com/python/cpython/issues/93096]: Removed undocumented python -m codecs. Use python -m unittest test.test_codecs.EncodedFileTest instead.

• gh-94207 [https://github.com/python/cpython/issues/94207]: Made _struct.Struct GC-tracked in order to fix a reference leak in the _struct module.

• gh-93096 [https://github.com/python/cpython/issues/93096]: Removed undocumented -t argument of python -m base64. Use python -m unittest test.test_base64.LegacyBase64TestCase.test_encodebytes instead.

• gh-94226 [https://github.com/python/cpython/issues/94226]: Remove the locale.format() function, deprecated in Python 3.7: use locale.format_string() instead. Patch by Victor Stinner.

• gh-94199 [https://github.com/python/cpython/issues/94199]: Remove the ssl.match_hostname() function. The ssl.match_hostname() was deprecated in Python 3.7. OpenSSL performs hostname matching since Python 3.7, Python no longer uses the ssl.match_hostname() function. Patch by Victor Stinner.

• gh-94214 [https://github.com/python/cpython/issues/94214]: Document the context object used in the venv.EnvBuilder class, and add the new environment's library path to it.

• gh-94199 [https://github.com/python/cpython/issues/94199]: Remove the ssl.wrap_socket() function, deprecated in Python 3.7: instead, create a ssl.SSLContext object and call its ssl.SSLContext.wrap_socket method. Any package that still uses ssl.wrap_socket() is broken and insecure. The function neither sends a SNI TLS extension nor validates server hostname. Code is subject to CWE 295 [https://cwe.mitre.org/data/definitions/295.html] Improper Certificate Validation. Patch by Victor Stinner.

• gh-94199 [https://github.com/python/cpython/issues/94199]: Remove the ssl.RAND_pseudo_bytes() function, deprecated in Python 3.6: use os.urandom() or ssl.RAND_bytes() instead. Patch by Victor Stinner.

• gh-94199 [https://github.com/python/cpython/issues/94199]: hashlib: Remove the pure Python implementation of hashlib.pbkdf2_hmac(), deprecated in Python 3.10. Python 3.10 and newer requires OpenSSL 1.1.1 ( PEP 644 [https://peps.python.org/pep-0644/]): this OpenSSL version provides a C implementation of pbkdf2_hmac() which is faster. Patch by Victor Stinner.

• gh-94196 [https://github.com/python/cpython/issues/94196]: gzip: Remove the filename attribute of gzip.GzipFile, deprecated since Python 2.6, use the name attribute instead. In write mode, the filename attribute added '.gz' file extension if it was not present. Patch by Victor Stinner.

• gh-94182 [https://github.com/python/cpython/issues/94182]: run the asyncio.PidfdChildWatcher on the running loop, this allows event loops to run subprocesses when there is no default event loop running on the main thread

• gh-94169 [https://github.com/python/cpython/issues/94169]: Remove io.OpenWrapper and _pyio.OpenWrapper, deprecated in Python 3.10: just use open() instead. The open() (io.open()) function is a builtin function. Since Python 3.10, _pyio.open() is also a static method. Patch by Victor Stinner.

• gh-91742 [https://github.com/python/cpython/issues/91742]: Fix pdb crash after jump caused by a null pointer dereference. Patch by Kumar Aditya.

• gh-94101 [https://github.com/python/cpython/issues/94101]: Manual instantiation of ssl.SSLSession objects is no longer allowed as it lead to misconfigured instances that crashed the interpreter when attributes where accessed on them.

• gh-84753 [https://github.com/python/cpython/issues/84753]: inspect.iscoroutinefunction(), inspect.isgeneratorfunction(), and inspect.isasyncgenfunction() now properly return True for duck-typed function-like objects like instances of unittest.mock.AsyncMock.

This makes inspect.iscoroutinefunction() consistent with the behavior of asyncio.iscoroutinefunction(). Patch by Mehdi ABAAKOUK.

• gh-94028 [https://github.com/python/cpython/issues/94028]: Fix a regression in the sqlite3 where statement objects were not properly cleared and reset after use in cursor iters. The regression was introduced by PR 27884 in Python 3.11a1. Patch by Erlend E. Aasland.

• gh-93973 [https://github.com/python/cpython/issues/93973]: Add keyword argument all_errors to asyncio.create_connection so that multiple connection errors can be raised as an ExceptionGroup.

• gh-93963 [https://github.com/python/cpython/issues/93963]: Officially deprecate from importlib.abc classes moved to importlib.resources.abc.

• gh-93858 [https://github.com/python/cpython/issues/93858]: Prevent error when activating venv in nested fish instances.

• gh-93820 [https://github.com/python/cpython/issues/93820]: Pickle enum.Flag by name.

• gh-93847 [https://github.com/python/cpython/issues/93847]: Fix repr of enum of generic aliases.

• gh-91404 [https://github.com/python/cpython/issues/91404]: Revert the re memory leak when a match is terminated by a signal or memory allocation failure as the implemented fix caused a major performance regression.

• gh-83499 [https://github.com/python/cpython/issues/83499]: Fix double closing of file description in tempfile.

• gh-93820 [https://github.com/python/cpython/issues/93820]: Fixed a regression when copy.copy()-ing enum.Flag with multiple flag members.

• gh-79512 [https://github.com/python/cpython/issues/79512]: Fixed names and __module__ value of weakref classes ReferenceType, ProxyType, CallableProxyType. It makes them pickleable.

• gh-91389 [https://github.com/python/cpython/issues/91389]: Fix an issue where dis utilities could report missing or incorrect position information in the presence of CACHE entries.

• gh-93626 [https://github.com/python/cpython/issues/93626]: Set __future__.annotations to have a None mandatoryRelease to indicate that it is currently 'TBD'.

• gh-90473 [https://github.com/python/cpython/issues/90473]: Emscripten and WASI have no home directory and cannot provide PEP 370 [https://peps.python.org/pep-0370/] user site directory.

• gh-90494 [https://github.com/python/cpython/issues/90494]: copy.copy() and copy.deepcopy() now always raise a TypeError if __reduce__() returns a tuple with length 6 instead of silently ignore the 6th item or produce incorrect result.

• gh-90549 [https://github.com/python/cpython/issues/90549]: Fix a multiprocessing bug where a global named resource (such as a semaphore) could leak when a child process is spawned (as opposed to forked).

• gh-93521 [https://github.com/python/cpython/issues/93521]: Fixed a case where dataclasses would try to add __weakref__ into the __slots__ for a dataclass that specified weakref_slot=True when it was already defined in one of its bases. This resulted in a TypeError upon the new class being created.

• gh-79579 [https://github.com/python/cpython/issues/79579]: sqlite3 now correctly detects DML queries with leading comments. Patch by Erlend E. Aasland.

• gh-93421 [https://github.com/python/cpython/issues/93421]: Update sqlite3.Cursor.rowcount when a DML statement has run to completion. This fixes the row count for SQL queries like UPDATE … RETURNING. Patch by Erlend E. Aasland.

• gh-93475 [https://github.com/python/cpython/issues/93475]: Expose FICLONE and FICLONERANGE constants in fcntl. Patch by Illia Volochii.

• gh-93370 [https://github.com/python/cpython/issues/93370]: Deprecate sqlite3.version and sqlite3.version_info.

• gh-91810 [https://github.com/python/cpython/issues/91810]: Suppress writing an XML declaration in open files in ElementTree.write() with encoding='unicode' and xml_declaration=None.

• gh-91162 [https://github.com/python/cpython/issues/91162]: Support splitting of unpacked arbitrary-length tuple over TypeVar and TypeVarTuple parameters. For example:

  • A[T, Ts][tuple[int, …]] -> A[int, *tuple[int, …]]

  • A[*Ts, T][*tuple[int, …]] -> A[*tuple[int, …], int]

• gh-93353 [https://github.com/python/cpython/issues/93353]: Fix the importlib.resources.as_file() context manager to remove the temporary file if destroyed late during Python finalization: keep a local reference to the os.remove() function. Patch by Victor Stinner.

• gh-83658 [https://github.com/python/cpython/issues/83658]: Make multiprocessing.Pool raise an exception if maxtasksperchild is not None or a positive int.

• gh-93312 [https://github.com/python/cpython/issues/93312]: Add os.PIDFD_NONBLOCK flag to open a file descriptor for a process with os.pidfd_open() in nonblocking mode. Patch by Kumar Aditya.

• gh-88123 [https://github.com/python/cpython/issues/88123]: Implement Enum.__contains__ that returns True or False to replace the deprecated behaviour that would sometimes raise a TypeError.

• gh-93297 [https://github.com/python/cpython/issues/93297]: Make asyncio task groups prevent child tasks from being GCed

• gh-85308 [https://github.com/python/cpython/issues/85308]: Changed argparse.ArgumentParser to use filesystem encoding and error handler instead of default text encoding to read arguments from file (e.g. fromfile_prefix_chars option). This change affects Windows; argument file should be encoded with UTF-8 instead of ANSI Codepage.

• gh-93156 [https://github.com/python/cpython/issues/93156]: Accessing the pathlib.PurePath.parents sequence of an absolute path using negative index values produced incorrect results.

• gh-93162 [https://github.com/python/cpython/issues/93162]: Add the ability for logging.config.dictConfig() to usefully configure QueueHandler and QueueListener as a pair, and add logging.getHandlerByName() and logging.getHandlerNames() APIs to allow access to handlers by name.

• gh-93243 [https://github.com/python/cpython/issues/93243]: The smtpd module was removed per the schedule in PEP 594 [https://peps.python.org/pep-0594/].

• gh-92886 [https://github.com/python/cpython/issues/92886]: Replace assert statements with raise AssertionError() in BaseHandler so that the tested behaviour is maintained running with optimizations (-O).

• gh-90155 [https://github.com/python/cpython/issues/90155]: Fix broken asyncio.Semaphore when acquire is cancelled.

• gh-90817 [https://github.com/python/cpython/issues/90817]: The locale.resetlocale() function is deprecated and will be removed in Python 3.13. Use locale.setlocale(locale.LC_ALL, "") instead. Patch by Victor Stinner.

• gh-91513 [https://github.com/python/cpython/issues/91513]: Added taskName attribute to logging module for use with asyncio tasks.

• gh-74696 [https://github.com/python/cpython/issues/74696]: shutil.make_archive() no longer temporarily changes the current working directory during creation of standard .zip or tar archives.

• gh-92728 [https://github.com/python/cpython/issues/92728]: The re.template() function and the corresponding re.TEMPLATE and re.T flags are restored after they were removed in 3.11.0b1, but they are now deprecated, so they might be removed from Python 3.13.

• gh-93033 [https://github.com/python/cpython/issues/93033]: Search in some strings (platform dependent i.e [U+0xFFFF, U+0x0100] on Windows or [U+0xFFFFFFFF, U+0x00010000] on Linux 64-bit) are now up to 10 times faster.

• gh-89973 [https://github.com/python/cpython/issues/89973]: Fix re.error raised in fnmatch if the pattern contains a character range with upper bound lower than lower bound (e.g. [c-a]). Now such ranges are interpreted as empty ranges.

• gh-93044 [https://github.com/python/cpython/issues/93044]: No longer convert the database argument of sqlite3.connect() to bytes before passing it to the factory.

• gh-93010 [https://github.com/python/cpython/issues/93010]: In a very special case, the email package tried to append the nonexistent InvalidHeaderError to the defect list. It should have been InvalidHeaderDefect.

• gh-92986 [https://github.com/python/cpython/issues/92986]: Fix ast.unparse() when ImportFrom.level is None

• gh-92932 [https://github.com/python/cpython/issues/92932]: Now dis() and get_instructions() handle operand values for instructions prefixed by EXTENDED_ARG_QUICK. Patch by Sam Gross and Donghee Na.

• gh-92675 [https://github.com/python/cpython/issues/92675]: Fix venv.ensure_directories() to accept pathlib.Path arguments in addition to str paths. Patch by David Foster.

• gh-87901 [https://github.com/python/cpython/issues/87901]: Removed the encoding argument from os.popen() that was added in 3.11b1.

• gh-91922 [https://github.com/python/cpython/issues/91922]: Fix function sqlite.connect() and the sqlite.Connection constructor on non-UTF-8 locales. Also, they now support bytes paths non-decodable with the current FS encoding.

• gh-92869 [https://github.com/python/cpython/issues/92869]: Added c_time_t to ctypes, which has the same size as the time_t type in C.

• gh-92839 [https://github.com/python/cpython/issues/92839]: Fixed crash resulting from calling bisect.insort() or bisect.insort_left() with the key argument not equal to None.

• gh-90473 [https://github.com/python/cpython/issues/90473]: subprocess now fails early on Emscripten and WASI platforms to work around missing os.pipe() on WASI.

• gh-89325 [https://github.com/python/cpython/issues/89325]: Removed many old deprecated unittest features: TestCase method aliases, undocumented and broken TestCase method assertDictContainsSubset, undocumented TestLoader.loadTestsFromModule parameter useloadtests, and an underscored alias of the TextTestResult class.

• gh-92734 [https://github.com/python/cpython/issues/92734]: Allow multi-element reprs emitted by reprlib to be pretty-printed using configurable indentation.

• gh-92671 [https://github.com/python/cpython/issues/92671]: Fixed ast.unparse() for empty tuples in the assignment target context.

• gh-91581 [https://github.com/python/cpython/issues/91581]: utcfromtimestamp() no longer attempts to resolve fold in the pure Python implementation, since the fold is never 1 in UTC. In addition to being slightly faster in the common case, this also prevents some errors when the timestamp is close to datetime.min. Patch by Paul Ganssle.

• gh-86388 [https://github.com/python/cpython/issues/86388]: Removed randrange() functionality deprecated since Python 3.10. Formerly, randrange(10.0) losslessly converted to randrange(10). Now, it raises a TypeError. Also, the exception raised for non-integral values such as randrange(10.5) or randrange('10') has been changed from ValueError to TypeError.

• gh-90385 [https://github.com/python/cpython/issues/90385]: Add pathlib.Path.walk() as an alternative to os.walk().

• gh-92550 [https://github.com/python/cpython/issues/92550]: Fix pathlib.Path.rglob() for empty pattern.

• gh-92591 [https://github.com/python/cpython/issues/92591]: Allow logging filters to return a logging.LogRecord instance so that filters attached to logging.Handlers can enrich records without side effects on other handlers.

• gh-92445 [https://github.com/python/cpython/issues/92445]: Fix a bug in argparse where nargs="*" would raise an error instead of returning an empty list when 0 arguments were supplied if choice was also defined in parser.add_argument.

• gh-92547 [https://github.com/python/cpython/issues/92547]: Remove undocumented sqlite3 features deprecated in Python 3.10:

  • sqlite3.enable_shared_cache()

  • sqlite3.OptimizedUnicode

Patch by Erlend E. Aasland.

• gh-92530 [https://github.com/python/cpython/issues/92530]: Fix an issue that occurred after interrupting threading.Condition.notify().

• gh-92531 [https://github.com/python/cpython/issues/92531]: The statistics.median_grouped() function now always return a float. Formerly, it did not convert the input type when for sequences of length one.

• gh-84131 [https://github.com/python/cpython/issues/84131]: The pathlib.Path deprecated method link_to has been removed. Use 3.10's hardlink_to() method instead as its semantics are consistent with that of symlink_to().

• gh-89336 [https://github.com/python/cpython/issues/89336]: Removed configparser module APIs: the SafeConfigParser class alias, the ParsingError.filename property and parameter, and the ConfigParser.readfp method, all of which were deprecated since Python 3.2.

• gh-92391 [https://github.com/python/cpython/issues/92391]: Add __class_getitem__() to csv.DictReader and csv.DictWriter, allowing them to be parameterized at runtime. Patch by Marc Mueller.

• gh-91968 [https://github.com/python/cpython/issues/91968]: Add SO_RTABLE and SO_USER_COOKIE constants to socket.

• gh-91810 [https://github.com/python/cpython/issues/91810]: ElementTree method write() and function tostring() now use the text file's encoding ("UTF-8" if not available) instead of locale encoding in XML declaration when encoding="unicode" is specified.

• gh-81790 [https://github.com/python/cpython/issues/81790]: os.path.splitdrive() now understands DOS device paths with UNC links (beginning \?\UNC\). Contributed by Barney Gale.

• gh-91760 [https://github.com/python/cpython/issues/91760]: Apply more strict rules 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.

• gh-90622 [https://github.com/python/cpython/issues/90622]: Worker processes for concurrent.futures.ProcessPoolExecutor are no longer spawned on demand (a feature added in 3.9) when the multiprocessing context start method is "fork" as that can lead to deadlocks in the child processes due to a fork happening while threads are running.

• gh-91577 [https://github.com/python/cpython/issues/91577]: Move imports in SharedMemory methods to module level so that they can be executed late in python finalization.

• gh-91581 [https://github.com/python/cpython/issues/91581]: Remove an unhandled error case in the C implementation of calls to datetime.fromtimestamp with no time zone (i.e. getting a local time from an epoch timestamp). This should have no user-facing effect other than giving a possibly more accurate error message when called with timestamps that fall on 10000-01-01 in the local time. Patch by Paul Ganssle.

• gh-91539 [https://github.com/python/cpython/issues/91539]: Improve performance of urllib.request.getproxies_environment when there are many environment variables

• gh-91524 [https://github.com/python/cpython/issues/91524]: Speed up the regular expression substitution (functions re.sub() and re.subn() and corresponding re.Pattern methods) for replacement strings containing group references by 2—3 times.

• gh-91447 [https://github.com/python/cpython/issues/91447]: Fix findtext in the xml module to only give an empty string when the text attribute is set to None.

• gh-91456 [https://github.com/python/cpython/issues/91456]: Deprecate current default auto() behavior: In 3.13 the default will be for for auto() to always return the largest member value incremented by 1, and to raise if incompatible value types are used.

• bpo-47231 [https://bugs.python.org/issue?@action=redirect&bpo=47231]: Fixed an issue with inconsistent trailing slashes in tarfile longname directories.

• bpo-39064 [https://bugs.python.org/issue?@action=redirect&bpo=39064]: zipfile.ZipFile now raises zipfile.BadZipFile instead of ValueError when reading a corrupt zip file in which the central directory offset is negative.

• bpo-41287 [https://bugs.python.org/issue?@action=redirect&bpo=41287]: Fix handling of the doc argument in subclasses of property().

• gh-90005 [https://github.com/python/cpython/issues/90005]: ctypes dependency libffi is now detected with pkg-config.

• bpo-32547 [https://bugs.python.org/issue?@action=redirect&bpo=32547]: The constructors for DictWriter and DictReader now coerce the fieldnames argument to a list if it is an iterator.

• bpo-35540 [https://bugs.python.org/issue?@action=redirect&bpo=35540]: Fix dataclasses.asdict() crash when collections.defaultdict is present in the attributes.

• bpo-47063 [https://bugs.python.org/issue?@action=redirect&bpo=47063]: Add an index_pages parameter to support using non-default index page names.

• bpo-47025 [https://bugs.python.org/issue?@action=redirect&bpo=47025]: Drop support for bytes on sys.path.

• bpo-46951 [https://bugs.python.org/issue?@action=redirect&bpo=46951]: Order the contents of zipapp archives, to make builds more reproducible.

• bpo-42777 [https://bugs.python.org/issue?@action=redirect&bpo=42777]: Implement pathlib.Path.is_mount() for Windows paths.

• bpo-46755 [https://bugs.python.org/issue?@action=redirect&bpo=46755]: In QueueHandler, clear stack_info from LogRecord to prevent stack trace from being written twice.

• bpo-45393 [https://bugs.python.org/issue?@action=redirect&bpo=45393]: Fix the formatting for await x and not x in the operator precedence table when using the help() system.

• bpo-46642 [https://bugs.python.org/issue?@action=redirect&bpo=46642]: Improve error message when trying to subclass an instance of typing.TypeVar, typing.ParamSpec, typing.TypeVarTuple, etc. Based on patch by Gregory Beauregard.

• bpo-46364 [https://bugs.python.org/issue?@action=redirect&bpo=46364]: Restrict use of sockets instead of pipes for stdin of subprocesses created by asyncio to AIX platform only.

• bpo-28249 [https://bugs.python.org/issue?@action=redirect&bpo=28249]: Set doctest.DocTest.lineno to None when an object does not have __doc__.

• bpo-46197 [https://bugs.python.org/issue?@action=redirect&bpo=46197]: Fix ensurepip environment isolation for subprocess running pip.

• bpo-45924 [https://bugs.python.org/issue?@action=redirect&bpo=45924]: Fix asyncio incorrect traceback when future's exception is raised multiple times. Patch by Kumar Aditya.

• bpo-45046 [https://bugs.python.org/issue?@action=redirect&bpo=45046]: Add support of context managers in unittest: methods enterContext() and enterClassContext() of class TestCase, method enterAsyncContext() of class IsolatedAsyncioTestCase and function unittest.enterModuleContext().

• bpo-44173 [https://bugs.python.org/issue?@action=redirect&bpo=44173]: Enable fast seeking of uncompressed unencrypted zipfile.ZipExtFile

• bpo-42627 [https://bugs.python.org/issue?@action=redirect&bpo=42627]: Fix incorrect parsing of Windows registry proxy settings

• bpo-42047 [https://bugs.python.org/issue?@action=redirect&bpo=42047]: Add threading.get_native_id() support for DragonFly BSD. Patch by David Carlier.

• bpo-14243 [https://bugs.python.org/issue?@action=redirect&bpo=14243]: The tempfile.NamedTemporaryFile function has a new optional parameter delete_on_close

• bpo-41246 [https://bugs.python.org/issue?@action=redirect&bpo=41246]: Give the same callback function for when the overlapped operation is done to the functions recv, recv_into, recvfrom, sendto, send and sendfile inside IocpProactor.

• bpo-39264 [https://bugs.python.org/issue?@action=redirect&bpo=39264]: Fixed collections.UserDict.get() to not call _missing_() when a value is not found. This matches the behavior of dict. Patch by Bar Harel.

• bpo-38693 [https://bugs.python.org/issue?@action=redirect&bpo=38693]: importlib now uses fstrings internally instead of str.format.

• bpo-38267 [https://bugs.python.org/issue?@action=redirect&bpo=38267]: Add timeout parameter to asyncio.loop.shutdown_default_executor(). The default value is None, which means the executor will be given an unlimited amount of time. When called from asyncio.Runner or asyncio.run(), the default timeout is 5 minutes.

• bpo-34828 [https://bugs.python.org/issue?@action=redirect&bpo=34828]: sqlite3.Connection.iterdump() now handles databases that use AUTOINCREMENT in one or more tables.

• bpo-32990 [https://bugs.python.org/issue?@action=redirect&bpo=32990]: Support reading wave files with the WAVE_FORMAT_EXTENSIBLE format in the wave module.

• bpo-26253 [https://bugs.python.org/issue?@action=redirect&bpo=26253]: Allow adjustable compression level for tarfile streams in tarfile.open().