This article explains the new features in Python 3.11, compared to 3.10.

For full details, see the :ref:`changelog <changelog>`.

When printing tracebacks, the interpreter will now point to the exact expression that caused the error instead of just the line. For example:

Traceback (most recent call last):
  File "distance.py", line 11, in <module>
    print(manhattan_distance(p1, p2))
          ^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "distance.py", line 6, in manhattan_distance
    return abs(point_1.x - point_2.x) + abs(point_1.y - point_2.y)
                           ^^^^^^^^^
AttributeError: 'NoneType' object has no attribute 'x'

Previous versions of the interpreter would point to just the line making it ambiguous which object was None. These enhanced errors can also be helpful when dealing with deeply nested dictionary objects and multiple function calls,

Traceback (most recent call last):
  File "query.py", line 37, in <module>
    magic_arithmetic('foo')
    ^^^^^^^^^^^^^^^^^^^^^^^
  File "query.py", line 18, in magic_arithmetic
    return add_counts(x) / 25
           ^^^^^^^^^^^^^
  File "query.py", line 24, in add_counts
    return 25 + query_user(user1) + query_user(user2)
                ^^^^^^^^^^^^^^^^^
  File "query.py", line 32, in query_user
    return 1 + query_count(db, response['a']['b']['c']['user'], retry=True)
                               ~~~~~~~~~~~~~~~~~~^^^^^
TypeError: 'NoneType' object is not subscriptable

as well as complex arithmetic expressions:

Traceback (most recent call last):
  File "calculation.py", line 54, in <module>
    result = (x / y / z) * (a / b / c)
              ~~~~~~^~~
ZeroDivisionError: division by zero

See PEP 657 for more details. (Contributed by Pablo Galindo, Batuhan Taskaya and Ammar Askar in :issue:`43950`.)

The information used by the enhanced traceback feature is made available as a general API that can be used to correlate bytecode instructions with source code. This information can be retrieved using:

• The :meth:`codeobject.co_positions` method in Python.
• The :c:func:`PyCode_Addr2Location` function in the C-API.

The :option:`-X` no_debug_ranges option and the environment variable :envvar:`PYTHONNODEBUGRANGES` can be used to disable this feature.

See PEP 657 for more details. (Contributed by Pablo Galindo, Batuhan Taskaya and Ammar Askar in :issue:`43950`.)

• Asynchronous comprehensions are now allowed inside comprehensions in asynchronous functions. Outer comprehensions implicitly become asynchronous. (Contributed by Serhiy Storchaka in :issue:`33346`.)
• A :exc:`TypeError` is now raised instead of an :exc:`AttributeError` in :meth:`contextlib.ExitStack.enter_context` and :meth:`contextlib.AsyncExitStack.enter_async_context` for objects which do not support the :term:`context manager` or :term:`asynchronous context manager` protocols correspondingly. (Contributed by Serhiy Storchaka in :issue:`44471`.)
• A :exc:`TypeError` is now raised instead of an :exc:`AttributeError` in :keyword:`with` and :keyword:`async with` statements for objects which do not support the :term:`context manager` or :term:`asynchronous context manager` protocols correspondingly. (Contributed by Serhiy Storchaka in :issue:`12022`.)

• Special methods :meth:`complex.__complex__` and :meth:`bytes.__bytes__` are implemented to support :class:`typing.SupportsComplex` and :class:`typing.SupportsBytes` protocols. (Contributed by Mark Dickinson and Dong-hee Na in :issue:`24234`.)
• siphash13 is added as a new internal hashing algorithms. It's has similar security properties as siphash24 but it is slightly faster for long inputs. str, bytes, and some other types now use it as default algorithm for hash(). PEP 552 hash-based pyc files now use siphash13, too. (Contributed by Inada Naoki in :issue:`29410`.)
• When an active exception is re-raised by a :keyword:`raise` statement with no parameters, the traceback attached to this exception is now always sys.exc_info()[1].__traceback__. This means that changes made to the traceback in the current :keyword:`except` clause are reflected in the re-raised exception. (Contributed by Irit Katriel in :issue:`45711`.)

• None yet.

• Support PEP 515-style initialization of :class:`~fractions.Fraction` from string. (Contributed by Sergey B Kirpichev in :issue:`44258`.)
• :class:`~fractions.Fraction` now implements an __int__ method, so that an isinstance(some_fraction, typing.SupportsInt) check passes. (Contributed by Mark Dickinson in :issue:`44547`.)

• Add :func:`inspect.getmembers_static`: return all members without triggering dynamic lookup via the descriptor protocol. (Contributed by Weipeng Hong in :issue:`30533`.)

• Add :func:`math.exp2`: return 2 raised to the power of x. (Contributed by Gideon Mitchell in :issue:`45917`.)
• Add :func:`math.cbrt`: return the cube root of x. (Contributed by Ajith Ramachandran in :issue:`44357`.)
• The behaviour of two :func:`math.pow` corner cases was changed, for consistency with the IEEE 754 specification. The operations math.pow(0.0, -math.inf) and math.pow(-0.0, -math.inf) now return inf. Previously they raised :exc:`ValueError`. (Contributed by Mark Dickinson in :issue:`44339`.)

• A new function operator.call has been added, such that operator.call(obj, *args, **kwargs) == obj(*args, **kwargs). (Contributed by Antony Lee in :issue:`44019`.)

• On Windows, :func:`os.urandom` now uses BCryptGenRandom(), instead of CryptGenRandom() which is deprecated. (Contributed by Dong-hee Na in :issue:`44611`.)

• You can now disable the authorizer by passing :const:`None` to :meth:`~sqlite3.Connection.set_authorizer`. (Contributed by Erlend E. Aasland in :issue:`44491`.)
• Collation name :meth:`~sqlite3.Connection.create_collation` can now contain any Unicode character. Collation names with invalid characters now raise :exc:`UnicodeEncodeError` instead of :exc:`sqlite3.ProgrammingError`. (Contributed by Erlend E. Aasland in :issue:`44688`.)
• :mod:`sqlite3` exceptions now include the SQLite extended error code as :attr:`~sqlite3.Error.sqlite_errorcode` and the SQLite error name as :attr:`~sqlite3.Error.sqlite_errorname`. (Contributed by Aviv Palivoda, Daniel Shahaf, and Erlend E. Aasland in :issue:`16379` and :issue:`24139`.)
• Add :meth:`~sqlite3.Connection.setlimit` and :meth:`~sqlite3.Connection.getlimit` to :class:`sqlite3.Connection` for setting and getting SQLite limits by connection basis. (Contributed by Erlend E. Aasland in :issue:`45243`.)
• :mod:`sqlite3` now sets :attr:`sqlite3.threadsafety` based on the default threading mode the underlying SQLite library has been compiled with. (Contributed by Erlend E. Aasland in :issue:`45613`.)
• :mod:`sqlite3` C callbacks now use unraisable exceptions if callback tracebacks are enabled. Users can now register an :func:`unraisable hook handler <sys.unraisablehook>` to improve their debug experience. (Contributed by Erlend E. Aasland in :issue:`45828`.)

• :func:`sys.exc_info` now derives the type and traceback fields from the value (the exception instance), so when an exception is modified while it is being handled, the changes are reflected in the results of subsequent calls to :func:`exc_info`. (Contributed by Irit Katriel in :issue:`45711`.)

• On Unix, if the sem_clockwait() function is available in the C library (glibc 2.30 and newer), the :meth:`threading.Lock.acquire` method now uses the monotonic clock (:data:`time.CLOCK_MONOTONIC`) for the timeout, rather than using the system clock (:data:`time.CLOCK_REALTIME`), to not be affected by system clock changes. (Contributed by Victor Stinner in :issue:`41710`.)

• On Unix, :func:`time.sleep` now uses the clock_nanosleep() or nanosleep() function, if available, which has a resolution of 1 nanosecond (10^-9 seconds), rather than using select() which has a resolution of 1 microsecond (10^-6 seconds). (Contributed by Benjamin Szőke and Victor Stinner in :issue:`21302`.)
• On Windows 8.1 and newer, :func:`time.sleep` now uses a waitable timer based on high-resolution timers which has a resolution of 100 nanoseconds (10^-7 seconds). Previously, it had a resolution of 1 millisecond (10^-3 seconds). (Contributed by Benjamin Szőke, Dong-hee Na, Eryk Sun and Victor Stinner in :issue:`21302` and :issue:`45429`.)

• The Unicode database has been updated to version 14.0.0. (:issue:`45190`).

• Compiler now optimizes simple C-style formatting with literal format containing only format codes %s, %r and %a and makes it as fast as corresponding f-string expression. (Contributed by Serhiy Storchaka in :issue:`28307`.)
• "Zero-cost" exceptions are implemented. The cost of try statements is almost eliminated when no exception is raised. (Contributed by Mark Shannon in :issue:`40222`.)
• Method calls with keywords are now faster due to bytecode changes which avoid creating bound method instances. Previously, this optimization was applied only to method calls with purely positional arguments. (Contributed by Ken Jin and Mark Shannon in :issue:`26110`, based on ideas implemented in PyPy.)
• Pure ASCII strings are now normalized in constant time by :func:`unicodedata.normalize`. (Contributed by Dong-hee Na in :issue:`44987`.)

• Replaced all numeric BINARY_* and INPLACE_* instructions with a single :opcode:`BINARY_OP` implementation.
• Added a new :opcode:`CALL_METHOD_KW` opcode. Calls a method in a similar fashion as :opcode:`CALL_METHOD`, but also supports keyword arguments. Works in tandem with :opcode:`LOAD_METHOD`.
• Removed COPY_DICT_WITHOUT_KEYS.
• :opcode:`MATCH_CLASS` and :opcode:`MATCH_KEYS` no longer push an additional boolean value indicating whether the match succeeded or failed. Instead, they indicate failure with :const:`None` (where a tuple of extracted values would otherwise be).
• Added :opcode:`COPY`, which pushes the i-th item to the top of the stack. The item is not removed from its original location.
• :opcode:`JUMP_IF_NOT_EXC_MATCH` no longer pops the active exception.

• The :mod:`lib2to3` package and 2to3 tool are now deprecated and may not be able to parse Python 3.10 or newer. See the PEP 617 (New PEG parser for CPython). (Contributed by Victor Stinner in :issue:`40360`.)

• :class:`webbrowser.MacOSX` is deprecated and will be removed in Python 3.13. It is untested and undocumented and also not used by webbrowser itself. (Contributed by Dong-hee Na in :issue:`42255`.)

• The behavior of returning a value from a :class:`~unittest.TestCase` and :class:`~unittest.IsolatedAsyncioTestCase` test methods (other than the default None value), is now deprecated.

• Deprecated the following :mod:`unittest` functions, scheduled for removal in Python 3.13:

  • :func:`unittest.findTestCases`
  • :func:`unittest.makeSuite`
  • :func:`unittest.getTestCaseNames`

  Use :class:`~unittest.TestLoader` method instead:

  • :meth:`unittest.TestLoader.loadTestsFromModule`
  • :meth:`unittest.TestLoader.loadTestsFromTestCase`
  • :meth:`unittest.TestLoader.getTestCaseNames`

  (Contributed by Erlend E. Aasland in :issue:`5846`.)

• The :meth:`turtle.RawTurtle.settiltangle` is deprecated since Python 3.1, it now emits a deprecation warning and will be removed in Python 3.13. Use :meth:`turtle.RawTurtle.tiltangle` instead (it was earlier incorrectly marked as deprecated, its docstring is now corrected). (Contributed by Hugo van Kemenade in :issue:`45837`.)

• :class:`smtpd.MailmanProxy` is now removed as it is unusable without an external module, mailman. (Contributed by Dong-hee Na in :issue:`35800`.)

• The binhex module, deprecated in Python 3.9, is now removed. The following :mod:`binascii` functions, deprecated in Python 3.9, are now also removed:

  • a2b_hqx(), b2a_hqx();
  • rlecode_hqx(), rledecode_hqx().

  The :func:`binascii.crc_hqx` function remains available.

  (Contributed by Victor Stinner in :issue:`45085`.)

• The distutils bdist_msi command, deprecated in Python 3.9, is now removed. Use bdist_wheel (wheel packages) instead. (Contributed by Hugo van Kemenade in :issue:`45124`.)

• Due to significant security concerns, the reuse_address parameter of :meth:`asyncio.loop.create_datagram_endpoint`, disabled in Python 3.9, is now entirely removed. This is because of the behavior of the socket option SO_REUSEADDR in UDP. (Contributed by Hugo van Kemenade in :issue:`45129`.)

• Removed :meth:`__getitem__` methods of :class:`xml.dom.pulldom.DOMEventStream`, :class:`wsgiref.util.FileWrapper` and :class:`fileinput.FileInput`, deprecated since Python 3.9. (Contributed by Hugo van Kemenade in :issue:`45132`.)

• Removed many old deprecated :mod:`unittest` features:

  • :class:`~unittest.TestCase` method aliases failUnlessEqual, failIfEqual, failUnless, failIf, failUnlessRaises, failUnlessAlmostEqual, failIfAlmostEqual (deprecated in Python 3.1), assertEquals, assertNotEquals, assert_, assertAlmostEquals, assertNotAlmostEquals, assertRegexpMatches, assertRaisesRegexp (deprecated in Python 3.2), and assertNotRegexpMatches (deprecated in Python 3.5).
  • Undocumented and broken :class:`~unittest.TestCase` method assertDictContainsSubset (deprecated in Python 3.2).
  • Undocumented :meth:`<unittest.TestLoader.loadTestsFromModule> TestLoader.loadTestsFromModule` parameter use_load_tests (deprecated and ignored since Python 3.2).
  • An alias of the :class:`~unittest.TextTestResult` class: _TextTestResult (deprecated in Python 3.2).

  (Contributed by Serhiy Storchaka in :issue:`45162`.)

• The following deprecated functions and methods are removed in the :mod:`gettext` module: :func:`~gettext.lgettext`, :func:`~gettext.ldgettext`, :func:`~gettext.lngettext` and :func:`~gettext.ldngettext`.

  Function :func:`~gettext.bind_textdomain_codeset`, methods :meth:`~gettext.NullTranslations.output_charset` and :meth:`~gettext.NullTranslations.set_output_charset`, and the codeset parameter of functions :func:`~gettext.translation` and :func:`~gettext.install` are also removed, since they are only used for the l*gettext() functions. (Contributed by Dong-hee Na and Serhiy Storchaka in :issue:`44235`.)

• Removed from the :mod:`configparser` module: the :class:`SafeConfigParser` class, the :attr:`filename` property of the :class:`ParsingError` class, the :meth:`readfp` method of the :class:`ConfigParser` class, deprecated since Python 3.2. (Contributed by Hugo van Kemenade in :issue:`45173`.)

• The :func:`@asyncio.coroutine <asyncio.coroutine>` :term:`decorator` enabling legacy generator-based coroutines to be compatible with async/await code. The function has been deprecated since Python 3.8 and the removal was initially scheduled for Python 3.10. Use :keyword:`async def` instead. (Contributed by Illia Volochii in :issue:`43216`.)

• :class:`asyncio.coroutines.CoroWrapper` used for wrapping legacy generator-based coroutine objects in the debug mode. (Contributed by Illia Volochii in :issue:`43216`.)

• Removed the deprecated split() method of :class:`_tkinter.TkappType`. (Contributed by Erlend E. Aasland in :issue:`38371`.)

• Removed from the :mod:`inspect` module:

  • the getargspec function, deprecated since Python 3.0; use :func:`inspect.signature` or :func:`inspect.getfullargspec` instead.
  • the formatargspec function, deprecated since Python 3.5; use the :func:`inspect.signature` function and :class:`Signature` object directly.
  • the undocumented Signature.from_callable and Signature.from_function functions, deprecated since Python 3.5; use the :meth:`Signature.from_callable() <inspect.Signature.from_callable>` method instead.

  (Contributed by Hugo van Kemenade in :issue:`45320`.)

• Remove the asyncore and asynchat modules, deprecated in Python 3.6: use the :mod:`asyncio` module instead. (Contributed by Victor Stinner in :issue:`28533`.)

• Remove the smtpd module, deprecated in Python 3.6: the aiosmtpd module can be used instead, it is based on asyncio. (Contributed by Victor Stinner in :issue:`28533`.)

This section lists previously described changes and other bugfixes that may require changes to your code.

• Prohibited passing non-:class:`concurrent.futures.ThreadPoolExecutor` executors to :meth:`loop.set_default_executor` following a deprecation in Python 3.8. (Contributed by Illia Volochii in :issue:`43234`.)
• :func:`open`, :func:`io.open`, :func:`codecs.open` and :class:`fileinput.FileInput` no longer accept 'U' ("universal newline") in the file mode. This flag was deprecated since Python 3.3. In Python 3, the "universal newline" is used by default when a file is open in text mode. The :ref:`newline parameter <open-newline-parameter>` of :func:`open` controls how universal newlines works. (Contributed by Victor Stinner in :issue:`37330`.)
• The :mod:`pdb` module now reads the :file:`.pdbrc` configuration file with the 'utf-8' encoding. (Contributed by Srinivas Reddy Thatiparthy (శ్రీనివాస్ రెడ్డి తాటిపర్తి) in :issue:`41137`.)
• When sorting using tuples as keys, the order of the result may differ from earlier releases if the tuple elements don't define a total ordering (see :ref:`expressions-value-comparisons` for information on total ordering). It's generally true that the result of sorting simply isn't well-defined in the absence of a total ordering on list elements.

• CPython can now be built with the ThinLTO option via --with-lto=thin. (Contributed by Dong-hee Na and Brett Holman in :issue:`44340`.)
• libpython is no longer linked against libcrypt. (Contributed by Mike Gilbert in :issue:`45433`.)
• Building Python now requires a C99 <math.h> header file providing the following functions: copysign(), hypot(), isfinite(), isinf(), isnan(), round(). (Contributed by Victor Stinner in :issue:`45440`.)
• Freelists for object structs can now be disabled. A new :program:`configure` option :option:`!--without-freelists` can be used to disable all freelists except empty tuple singleton. (Contributed by Christian Heimes in :issue:`45522`)
• Modules/Setup and Modules/makesetup have been improved and tied up. Extension modules can now be built through makesetup. All except some test modules can be linked statically into main binary or library. (Contributed by Brett Cannon and Christian Heimes in :issue:`45548`, :issue:`45570`, :issue:`45571`, and :issue:`43974`.)
• The build dependencies for :mod:`zlib`, :mod:`bz2`, and :mod:`lzma` are now detected by :program:`configure`. (Contributed by Christian Heimes in :issue:`45763`.)
• Build dependencies for :mod:`dbm` are now detected by :program:`configure`. libdb 3.x and 4.x are no longer supported. (Contributed by Christian Heimes in :issue:`45747`.)
• CPython now has experimental support for cross compiling to WebAssembly platform wasm32-emscripten. The effort is inspired by previous work like Pyodide. (Contributed by Christian Heimes and Ethan Smith in :issue:`40280`.)

• Add a new :c:func:`PyType_GetName` function to get type's short name. (Contributed by Hai Shi in :issue:`42035`.)
• Add a new :c:func:`PyType_GetQualName` function to get type's qualified name. (Contributed by Hai Shi in :issue:`42035`.)
• Add new :c:func:`PyThreadState_EnterTracing` and :c:func:`PyThreadState_LeaveTracing` functions to the limited C API to suspend and resume tracing and profiling. (Contributed by Victor Stinner in :issue:`43760`.)
• :c:func:`PyErr_SetExcInfo()` no longer uses the type and traceback arguments, the interpreter now derives those values from the exception instance (the value argument). The function still steals references of all three arguments. (Contributed by Irit Katriel in :issue:`45711`.)
• :c:func:`PyErr_GetExcInfo()` now derives the type and traceback fields of the result from the exception instance (the value field). (Contributed by Irit Katriel in :issue:`45711`.)

• The old trashcan macros (Py_TRASHCAN_SAFE_BEGIN/Py_TRASHCAN_SAFE_END) are now deprecated. They should be replaced by the new macros Py_TRASHCAN_BEGIN and Py_TRASHCAN_END.

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

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

  should migrate to the new macros as follows:

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

  Note that Py_TRASHCAN_BEGIN has a second argument which should be the deallocation function it is in.

  To support older Python versions in the same codebase, you can define the following macros and use them throughout the code (credit: these were copied from the mypy codebase):

  #if PY_MAJOR_VERSION >= 3 && PY_MINOR_VERSION >= 8
  #  define CPy_TRASHCAN_BEGIN(op, dealloc) Py_TRASHCAN_BEGIN(op, dealloc)
  #  define CPy_TRASHCAN_END(op) Py_TRASHCAN_END
  #else
  #  define CPy_TRASHCAN_BEGIN(op, dealloc) Py_TRASHCAN_SAFE_BEGIN(op)
  #  define CPy_TRASHCAN_END(op) Py_TRASHCAN_SAFE_END(op)
  #endif
  

• The :c:func:`PyType_Ready` function now raises an error if a type is defined with the :const:`Py_TPFLAGS_HAVE_GC` flag set but has no traverse function (:c:member:`PyTypeObject.tp_traverse`). (Contributed by Victor Stinner in :issue:`44263`.)

• Heap types with the :const:`Py_TPFLAGS_IMMUTABLETYPE` flag can now inherit the PEP 590 vectorcall protocol. Previously, this was only possible for :ref:`static types <static-types>`. (Contributed by Erlend E. Aasland in :issue:`43908`)

• Since :c:func:`Py_TYPE()` is changed to a inline static function, Py_TYPE(obj) = new_type must be replaced with Py_SET_TYPE(obj, new_type): see the :c:func:`Py_SET_TYPE()` function (available since Python 3.9). For backward compatibility, this macro can be used:

  #if PY_VERSION_HEX < 0x030900A4 && !defined(Py_SET_TYPE)
  static inline void _Py_SET_TYPE(PyObject *ob, PyTypeObject *type)
  { ob->ob_type = type; }
  #define Py_SET_TYPE(ob, type) _Py_SET_TYPE((PyObject*)(ob), type)
  #endif
  

  (Contributed by Victor Stinner in :issue:`39573`.)

• Since :c:func:`Py_SIZE()` is changed to a inline static function, Py_SIZE(obj) = new_size must be replaced with Py_SET_SIZE(obj, new_size): see the :c:func:`Py_SET_SIZE()` function (available since Python 3.9). For backward compatibility, this macro can be used:

  #if PY_VERSION_HEX < 0x030900A4 && !defined(Py_SET_SIZE)
  static inline void _Py_SET_SIZE(PyVarObject *ob, Py_ssize_t size)
  { ob->ob_size = size; }
  #define Py_SET_SIZE(ob, size) _Py_SET_SIZE((PyVarObject*)(ob), size)
  #endif
  

  (Contributed by Victor Stinner in :issue:`39573`.)

• <Python.h> no longer includes the header files <stdlib.h>, <stdio.h>, <errno.h> and <string.h> when the Py_LIMITED_API macro is set to 0x030b0000 (Python 3.11) or higher. C extensions should explicitly include the header files after #include <Python.h>. (Contributed by Victor Stinner in :issue:`45434`.)

• The non-limited API files cellobject.h, classobject.h, context.h, funcobject.h, genobject.h and longintrepr.h have been moved to the Include/cpython directory. Moreover, the eval.h header file was removed. These files must not be included directly, as they are already included in Python.h: :ref:`Include Files <api-includes>`. If they have been included directly, consider including Python.h instead. (Contributed by Victor Stinner in :issue:`35134`.)

• Deprecate the following functions to configure the Python initialization:

  • :c:func:`PySys_AddWarnOptionUnicode`
  • :c:func:`PySys_AddWarnOption`
  • :c:func:`PySys_AddXOption`
  • :c:func:`PySys_HasWarnOptions`
  • :c:func:`Py_SetPath`
  • :c:func:`Py_SetProgramName`
  • :c:func:`Py_SetPythonHome`
  • :c:func:`Py_SetStandardStreamEncoding`
  • :c:func:`_Py_SetProgramFullPath`

  Use the new :c:type:`PyConfig` API of the :ref:`Python Initialization Configuration <init-config>` instead (PEP 587). (Contributed by Victor Stinner in :issue:`44113`.)

• :c:func:`PyFrame_BlockSetup` and :c:func:`PyFrame_BlockPop` have been removed. (Contributed by Mark Shannon in :issue:`40222`.)

• Remove the following math macros using the errno variable:

  • Py_ADJUST_ERANGE1()
  • Py_ADJUST_ERANGE2()
  • Py_OVERFLOWED()
  • Py_SET_ERANGE_IF_OVERFLOW()
  • Py_SET_ERRNO_ON_MATH_ERROR()

  (Contributed by Victor Stinner in :issue:`45412`.)

• Remove Py_UNICODE_COPY() and Py_UNICODE_FILL() macros, deprecated since Python 3.3. Use PyUnicode_CopyCharacters() or memcpy() (wchar_t* string), and PyUnicode_Fill() functions instead. (Contributed by Victor Stinner in :issue:`41123`.)

• Remove the pystrhex.h header file. It only contains private functions. C extensions should only include the main <Python.h> header file. (Contributed by Victor Stinner in :issue:`45434`.)

• Remove the Py_FORCE_DOUBLE() macro. It was used by the Py_IS_INFINITY() macro. (Contributed by Victor Stinner in :issue:`45440`.)

• The following items are no longer available when :c:macro:`Py_LIMITED_API` is defined:

  • :c:func:`PyMarshal_WriteLongToFile`
  • :c:func:`PyMarshal_WriteObjectToFile`
  • :c:func:`PyMarshal_ReadObjectFromString`
  • :c:func:`PyMarshal_WriteObjectToString`
  • the Py_MARSHAL_VERSION macro

  These are not part of the :ref:`limited API <stable-abi-list>`.

  (Contributed by Victor Stinner in :issue:`45474`.)

• Exclude :c:func:`PyWeakref_GET_OBJECT` from the limited C API. It never worked since the :c:type:`PyWeakReference` structure is opaque in the limited C API. (Contributed by Victor Stinner in :issue:`35134`.)