Python Language Reference

3.12

The Python Language Reference is the official, authoritative specification of the Python programming language.

Python 3.12 was released in October 2023. It introduced the following new language features:

• new syntax for type parameters for functions (e.g., def func[T](x: T) -> T:) and classes (e.g., class C[T]:)
• the type statement, to define a type alias (e.g., type T = int | str)

See What’s New In Python 3.12 for more details.