Tuesday, May 19, 2020

Python 3.9.0b1 is now available for testing

On behalf of the entire Python development community, and the currently serving Python release team in particular, I’m pleased to announce the release of Python 3.9.0b1. Get it here:

https://www.python.org/downloads/release/python-390b1/


This is a beta preview of Python 3.9

Python 3.9 is still in development. This release, 3.9.0b1, is the first of four planned beta release previews.
Beta release previews are intended to give the wider community the opportunity to test new features and bug fixes and to prepare their projects to support the new feature release.

Call to action

We strongly encourage maintainers of third-party Python projects to test with 3.9 during the beta phase and report issues found to the Python bug tracker as soon as possible. While the release is planned to be feature complete entering the beta phase, it is possible that features may be modified or, in rare cases, deleted up until the start of the release candidate phase (2020-08-10). Our goal is have no ABI changes after beta 4 and as few code changes as possible after 3.9.0rc1, the first release candidate. To achieve that, it will be extremely important to get as much exposure for 3.9 as possible during the beta phase.
Please keep in mind that this is a preview release and its use is not recommended for production environments.

Major new features of the 3.9 series, compared to 3.8

Some of the new major new features and changes in Python 3.9 are:
  • PEP 584, Union Operators in dict
  • PEP 585, Type Hinting Generics In Standard Collections
  • PEP 593, Flexible function and variable annotations
  • PEP 602, Python adopts a stable annual release cadence
  • PEP 616, String methods to remove prefixes and suffixes
  • PEP 617, New PEG parser for CPython
  • BPO 38379, garbage collection does not block on resurrected objects;
  • BPO 38692, os.pidfd_open added that allows process management without races and signals;
  • BPO 39926, Unicode support updated to version 13.0.0;
  • BPO 1635741, when Python is initialized multiple times in the same process, it does not leak memory anymore;
  • A number of Python builtins (range, tuple, set, frozenset, list, dict) are now sped up using PEP 590 vectorcall;
  • A number of Python modules (_abc, audioop, _bz2, _codecs, _contextvars, _crypt, _functools, _json, _locale, operator, resource, time, _weakref) now use multiphase initialization as defined by PEP 489;
  • A number of standard library modules (audioop, ast, grp, _hashlib, pwd, _posixsubprocess, random, select, struct, termios, zlib) are now using the stable ABI defined by PEP 384.
  • (Hey, fellow core developer, if a feature you find important is missing from this list, let Łukasz know.)
The next pre-release, the second beta release of Python 3.9, will be 3.9.0b2. It is currently scheduled for 2020-06-08.

More resources

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

Thursday, May 14, 2020

Python 3.8.3 is now available

On behalf of the entire Python development community, and the currently serving Python release team in particular, I’m pleased to announce the release of Python 3.8.3, the third maintenance release of Python 3.8. You can find it here:


It contains two months worth of bug fixes. Detailed information about all changes made in 3.8.3 can be found in its change log. Note that compared to 3.8.2, version 3.8.3 also contains the changes introduced in 3.8.3rc1.

The Python 3.8 series is the newest feature release of the Python language, and it contains many new features and optimizations. See the “What’s New in Python 3.8” document for more information about features included in the 3.8 series.

Maintenance releases for the 3.8 series will continue at regular bi-monthly intervals, with 3.8.4 planned for mid-July 2020.

One more thing

Unless blocked on any critical issue, Monday May 18th will be the release date of Python 3.9.0 beta 1. It’s a special release because this is when we lock the feature set for Python 3.9. If you can help testing the current available alpha release, that would be very helpful:

We hope you enjoy the new Python 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.


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