Release date: Aug. 24, 2023

This is the fifth maintenance release of Python 3.11

Python 3.11.5 is the newest major release of the Python programming language, and it contains many new features and optimizations.

Security content in this release

• gh-108310: Fixed an issue where instances of ssl.SSLSocket were vulnerable to a bypass of the TLS handshake and included protections (like certificate verification) and treating sent unencrypted data as if it were post-handshake TLS encrypted data. Security issue reported as CVE-2023-40217 by Aapo Oksman. Patch by Gregory P. Smith.

Major new features of the 3.11 series, compared to 3.10

Some of the new major new features and changes in Python 3.11 are:

General changes

• PEP 657 -- Include Fine-Grained Error Locations in Tracebacks
• PEP 654 -- Exception Groups and except*
• PEP 680 -- tomllib: Support for Parsing TOML in the Standard Library
• gh-90908 -- Introduce task groups to asyncio
• gh-34627 -- Atomic grouping ((?>...)) and possessive quantifiers (*+, ++, ?+, {m,n}+) are now supported in regular expressions.
• The Faster CPython Project is already yielding some exciting results. Python 3.11 is up to 10-60% faster than Python 3.10. On average, we measured a 1.22x speedup on the standard benchmark suite. See Faster CPython for details.

Typing and typing language changes

• PEP 673 -- Self Type
• PEP 646 -- Variadic Generics
• PEP 675 -- Arbitrary Literal String Type
• PEP 655 -- Marking individual TypedDict items as required or potentially-missing
• PEP 681 -- Data Class Transforms

More resources

• Online Documentation
• PEP 664, 3.11 Release Schedule
• Report bugs at https://github.com/python/cpython/issues.
• Help fund Python and its community.

And now for something completely different

In physics, Larmor precession (named after Joseph Larmor) is the precession of the magnetic moment of an object about an external magnetic field. The phenomenon is conceptually similar to the precession of a tilted classical gyroscope in an external torque-exerting gravitational field. Objects with a magnetic moment also have angular momentum and effective internal electric current proportional to their angular momentum; these include electrons, protons, other fermions, many atomic and nuclear systems, as well as classical macroscopic systems.

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