New Features and Improvements in Python 3.11

Python 3.11 has been officially released, marking the latest step in the Python 3 series after the end of Python 2 support in 2020.

The new version delivers a speed increase of roughly 10‑60 % over Python 3.10, thanks to the "Faster CPython" project and the introduction of PEP 659, which adds a specializing adaptive interpreter that quickens frequently executed bytecode after a few calls.

Key language enhancements include:

More detailed error tracebacks with decorative annotations to help locate the source of errors.

Task groups for cleaner asynchronous code, building on the existing asyncio framework.

Five new type‑related PEPs (646, 655, 673, 675, 681) that expand generic typing, TypedDict handling, self‑type, literal string types, and dataclass conversion.

Native TOML configuration parsing via the new tomllib module, replacing the need for third‑party libraries.

Zero‑cost exceptions that make the try‑except block virtually free when no exception is raised, inspired by C++/Java mechanisms.

Exception groups that allow multiple exceptions to be raised and handled together.

Support for negative‑zero formatting in floating‑point output.

Performance‑focused improvements also reduce interpreter startup time and speed up module import, as demonstrated by micro‑benchmarks comparing Python 3.11 to 3.10.

Additional minor features include faster program launch, refined exception handling, and small string‑formatting tweaks.

For more details, refer to the official Python 3.11 documentation and the Faster‑CPython project repository.