Release Date: April 4, 2023

This is an early developer preview of Python 3.12.

Major new features of the 3.12 series, compared to 3.11

Python 3.12 is still in development. This release, 3.12.0a7 is the seventh and final alpha release of 3.12.

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 (2023-05-08) and, if necessary, may be modified or deleted up until the release candidate phase (2023-07-31). Please keep in mind that this is a preview release and its use is not recommended for production environments.

Many new features for Python 3.12 are still being planned and written. Among the new major new features and changes so far:

• 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.
• 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 (installed by default in virtualenvs and many other places) 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.)
• (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 3.12, see What's new in Python 3.12. The next pre-release of Python 3.12 will be 3.12.0b1, currently scheduled for 2023-05-08.

More resources

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

Note on the macOS Installer

Shortly after the release a cosmetic issue in the macOS installer was discovered. Since it does not affect the installed Python itself, merely the dialogs during installation, we have replaced the installer with a fixed version. If you downloaded the installer in the first day or so you may have received the old installer with a different size and md5 sum. The only difference with the new installer is the cosmetic issue, and there is no reason to uninstall and reinstall with the new installer.