Another big release day! Python 3.13.1 and 3.12.8 were regularly scheduled releases, but they do contain a few security fixes. That makes it a nice time to release the security-fix-only versions too, so everything is as secure as we can make it.

Alpha 2? But Alpha 1 only just came out!

https://www.python.org/downloads/release/python-3140a2/

This is an early developer preview of Python 3.14

Major new features of the 3.14 series, compared to 3.13

Python 3.14 is still in development. This release, 3.14.0a2 is the second of seven planned alpha releases.

Alpha releases are intended to make it easier to test the current state of new features and bug fixes and to test the release process.

During the alpha phase, features may be added up until the start of the beta phase (2025-05-06) and, if necessary, may be modified or deleted up until the release candidate phase (2025-07-22). Please keep in mind that this is a preview release and its use is not recommended for production environments.

Many new features for Python 3.14 are still being planned and written. Among the new major new features and changes so far:

• PEP 649: deferred evaluation of annotations
• PEP 741: Python configuration C API
• PEP 761: Python 3.14 and onwards no longer provides PGP signatures for release artifacts. Instead, Sigstore is recommended for verifiers.
• Improved error messages
• (Hey, fellow core developer, if a feature you find important is missing from this list, let Hugo know.)

The next pre-release of Python 3.14 will be 3.14.0a3, currently scheduled for 2024-12-17.

More resources

• Online documentation
• PEP 745, 3.14 Release Schedule
• Report bugs at https://github.com/python/cpython/issues
• Help fund Python and its community

Enjoy the new release

Thanks to all of the many volunteers who help make Python Development and these releases possible! Please consider supporting our efforts by volunteering yourself or through organisation contributions to the Python Software Foundation.

Regards from a chilly Helsinki with snow on the way,

Your release team,
Hugo van Kemenade
Ned Deily
Steve Dower
Łukasz Langa

It's now time for a new alpha of a new version of Python!

https://www.python.org/downloads/release/python-3140a1/

This is an early developer preview of Python 3.14

Major new features of the 3.14 series, compared to 3.13

Python 3.14 is still in development. This release, 3.14.0a1 is the first of seven planned alpha releases.

Alpha releases are intended to make it easier to test the current state of new features and bug fixes and to test the release process.

During the alpha phase, features may be added up until the start of the beta phase (2025-05-06) and, if necessary, may be modified or deleted up until the release candidate phase (2025-07-22). Please keep in mind that this is a preview release and its use is not recommended for production environments.

Many new features for Python 3.14 are still being planned and written. Among the new major new features and changes so far:

• PEP 649: deferred evaluation of annotations
• Improved error messages
• (Hey, fellow core developer, if a feature you find important is missing from this list, let Hugo know.)

The next pre-release of Python 3.14 will be 3.14.0a2, currently scheduled for 2024-11-19.

More resources

• Online documentation
• PEP 745, 3.14 Release Schedule
• Report bugs at https://github.com/python/cpython/issues
• Help fund Python and its community

Enjoy the new release

Thanks to all of the many volunteers who help make Python Development and these releases possible! Please consider supporting our efforts by volunteering yourself or through organization contributions to the Python Software Foundation.

Regards from a grey yet colourful Helsinki,

Your release team,
Hugo van Kemenade
Ned Deily
Steve Dower
Łukasz Langa

Python 3.13.0 is now available

I'm pleased to announce the release of Python 3.12.7:

https://www.python.org/downloads/release/python-3127/

This is the seventh maintenance release of Python 3.12

Python 3.12 is the newest major release of the Python programming language, and it contains many new features and optimizations. 3.12.7 is the latest maintenance release, containing more than 100 bugfixes, build improvements and documentation changes since 3.12.6.

Major new features of the 3.12 series, compared to 3.11

New features

• More flexible f-string parsing, allowing many things previously disallowed (PEP 701).
• Support for the buffer protocol in Python code (PEP 688).
• A new debugging/profiling API (PEP 669).
• Support for isolated subinterpreters with separate Global Interpreter Locks (PEP 684).
• Even more improved error messages. More exceptions potentially caused by typos now make suggestions to the user.
• Support for the Linux perf profiler to report Python function names in traces.
• Many large and small performance improvements (like PEP 709 and support for the BOLT binary optimizer), delivering an estimated 5% overall performance improvement.

Type annotations

• New type annotation syntax for generic classes (PEP 695).
• New override decorator for methods (PEP 698).

Deprecations

• The deprecated wstr and wstr_length members of the C implementation of unicode objects were removed, per PEP 623.
• In the unittest module, a number of long deprecated methods and classes were removed. (They had been deprecated since Python 3.1 or 3.2).
• The deprecated smtpd and distutils modules have been removed (see PEP 594 and PEP 632. The setuptools package continues to provide the distutils module.
• A number of other old, broken and deprecated functions, classes and methods have been removed.
• Invalid backslash escape sequences in strings now warn with SyntaxWarning instead of DeprecationWarning, making them more visible. (They will become syntax errors in the future.)
• The internal representation of integers has changed in preparation for performance enhancements. (This should not affect most users as it is an internal detail, but it may cause problems for Cython-generated code.)

For more details on the changes to Python 3.12, see What’s new in Python 3.12.

More resources

• Online Documentation.
• PEP 693, the Python 3.12 Release Schedule.
• Report bugs via GitHub Issues.
• Help fund Python directly or via GitHub Sponsors, and support the Python community.

Enjoy the new releases

Thanks to all of the many volunteers who help make Python Development and these releases possible! Please consider supporting our efforts by volunteering yourself or through organization contributions to the Python Software Foundation.

Your release team,
Thomas Wouters
Łukasz Langa
Ned Deily
Steve Dower

I'm pleased to announce the release of Python 3.13 release candidate 3 (instead of the expected final release).

https://www.python.org/downloads/release/python-3130rc3/

This is the final release candidate of Python 3.13.0

This release, 3.13.0rc3, is the final release preview (no really) of 3.13. This release is expected to become the final 3.13.0 release, barring any critical bugs being discovered. The official release of 3.13.0 is now scheduled for Monday, 2024-10-07.

This extra, unplanned release candidate exists because of a couple of last minute issues, primarily a significant performance regression in specific workloads due to the incremental cyclic garbage collector (introduced in the alpha releases). We decided to roll back the garbage collector change in 3.13 (and continuing work in 3.14 to improve it), apply a number of other important bug fixes, and roll out a new release candidate.

There will be no ABI changes from this point forward in the 3.13 series (and there haven't been any since the beta releases).

Call to action

We strongly encourage maintainers of Python projects to prepare their projects for 3.13 compatibilities during this phase, and where necessary publish Python 3.13 wheels on PyPI to be ready for the final release of 3.13.0. Any binary wheels built against Python 3.13.0rc1 and later will work with future versions of Python 3.13. As always, report any issues to the Python bug tracker.

Please keep in mind that this is a preview release and while it’s as close to the final release as we can get it, its use is not recommended for production environments.

Core developers: time to work on documentation now

• Are all your changes properly documented?
• Are they mentioned in What’s New?
• Did you notice other changes you know of to have insufficient documentation?

Major new features of the 3.13 series, compared to 3.12

Some of the new major new features and changes in Python 3.13 are:

New features

• A new and improved interactive interpreter, based on PyPy’s, featuring multi-line editing and color support, as well as colorized exception tracebacks.
• An experimental free-threaded build mode, which disables the Global Interpreter Lock, allowing threads to run more concurrently. The build mode is available as an experimental feature in the Windows and macOS installers as well.
• A preliminary, experimental JIT, providing the ground work for significant performance improvements.
• The locals() builtin function (and its C equivalent) now has well-defined semantics when mutating the returned mapping, which allows debuggers to operate more consistently.
• A modified version of mimalloc is now included, optional but enabled by default if supported by the platform, and required for the free-threaded build mode.
• Docstrings now have their leading indentation stripped, reducing memory use and the size of .pyc files. (Most tools handling docstrings already strip leading indentation.)
• The dbm module has a new dbm.sqlite3 backend that is used by default when creating new files.
• The minimum supported macOS version was changed from 10.9 to 10.13 (High Sierra). Older macOS versions will not be supported going forward.
• WASI is now a Tier 2 supported platform. Emscripten is no longer an officially supported platform (but Pyodide continues to support Emscripten).
• iOS is now a Tier 3 supported platform
• Android is now a Tier 3 supported platform as well.

Typing

• Support for type defaults in type parameters.
• A new type narrowing annotation, typing.TypeIs.
• A new annotation for read-only items in TypeDicts.
• A new annotation for marking deprecations in the type system.

Removals and new deprecations

• PEP 594 (Removing dead batteries from the standard library) scheduled removals of many deprecated modules: aifc, audioop, chunk, cgi, cgitb, crypt, imghdr, mailcap, msilib, nis, nntplib, ossaudiodev, pipes, sndhdr, spwd, sunau, telnetlib, uu, xdrlib, lib2to3.
• Many other removals of deprecated classes, functions and methods in various standard library modules.
• C API removals and deprecations. (Some removals present in alpha 1 were reverted in alpha 2, as the removals were deemed too disruptive at this time.)
• New deprecations, most of which are scheduled for removal from Python 3.15 or 3.16.

(Hey, fellow core developer, if a feature you find important is missing from this list, let Thomas know.)

For more details on the changes to Python 3.13, see What’s new in Python 3.13. The next release of Python 3.13 will be the official 3.13.0 release, currently scheduled for Monday, 2024-10-07.

More resources

• Online Documentation
• PEP 719, 3.13 Release Schedule
• Report bugs at Issues · python/cpython · GitHub.
• Help fund Python directly (or via GitHub Sponsors), and support the Python community.

Enjoy the new releases

Thanks to all of the many volunteers who help make Python Development and these releases possible! Please consider supporting our efforts by volunteering yourself or through organization contributions to the Python Software Foundation.

Your release team,

Thomas Wouters
Łukasz Langa
Ned Deily
Steve Dower