Python 3.13 alpha 3

We silently skipped releasing in December (it was too close to the holidays, a lot of people were away) so by date you may have been expecting alpha 4, but instead it’s:

This is an early developer preview of Python 3.13

Major new features of the 3.13 series, compared to 3.12

Python 3.13 is still in development. This release, 3.13.0a3, is the third of six 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 (2024-05-07) and, if necessary, may be modified or deleted up until the release candidate phase (2024-07-30). Please keep in mind that this is a preview release and its use is not recommended for production environments.

Many new features for Python 3.13 are still being planned and written. Work continues apace on both the work to remove the Global Interpeter Lock, and to improve Python performance. The most notable changes so far:

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

The next pre-release of Python 3.13 will be 3.13.0a4, currently scheduled for 2023-02-13.

More resources

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.

Regards from snowy Amsterdam,

Your release team,
Thomas Wouters @thomas
Ned Deily @nad
Steve Dower @steve.dower
Łukasz Langa @ambv


Thank you Thomas!

If possible, I would be happy if we could introduce os.cpu_count() and os.process_cpu_count() with the new environment variable PYTHON_CPU_COUNT or the new command-line option -X cpu_count through release news!

With these new features, Python becomes more cloud-friendly :slight_smile:


WASI build at Release CPython 3.13.0a3 w/ WASI SDK 20 · brettcannon/cpython-wasi-build · GitHub

CI images as usual here: Files · main · python-devs / ci-images · GitLab

It’s possible, but I don’t think these additions are major enough to be called out in the release announcement. They should be documented in What’s New, of course, but the release announcement tries to point out the things people should be excited or worried about.