Release Date: Nov. 5, 2021

This is an early developer preview of Python 3.11

Major new features of the 3.11 series, compared to 3.10

Python 3.11 is still in development. This release, 3.11.0a2 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 (2022-05-06) and, if necessary, may be modified or deleted up until the release candidate phase (2022-08-01). Please keep in mind that this is a preview release and its use is not recommended for production environments.

Many new features for Python 3.11 are still being planned and written. Among the new major new features and changes so far:

• PEP 657 -- Include Fine-Grained Error Locations in Tracebacks
• The Faster Cpython Project is already yielding some exciting results: this version of CPython 3.11 is ~12% faster on the geometric mean of the PyPerformance benchmarks, compared to 3.10.0.
• (Hey, fellow core developer, if a feature you find important is missing from this list, let Pablo know.)

The next pre-release of Python 3.11 will be 3.11.0a3, currently scheduled for Monday, 2021-12-06

More resources

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

And now for something completely different

In physical cosmology and astronomy, dark energy is an unknown form of energy that affects the universe on the largest scales. The first observational evidence for its existence came from measurements of supernovae, which showed that the universe does not expand at a constant rate; rather, the expansion of the universe is accelerating. Understanding the evolution of the universe requires knowledge of its starting conditions and its composition. Prior to these observations, it was thought that all forms of matter and energy in the universe would only cause the expansion to slow down over time.

Measurements of the cosmic microwave background suggest the universe began in a hot Big Bang, from which general relativity explains its evolution and the subsequent large-scale motion. Without introducing a new form of energy, there was no way to explain how an accelerating universe could be measured. Since the 1990s, dark energy has been the most accepted premise to account for the accelerated expansion.