New Typing Features in Python 3.13: ReadOnly, @warnings.deprecated, TypeIs, is_protocol, get_protocol_members, Default TypeVars, NoDefault, and Performance Improvements
Python 3.13 introduces a suite of typing enhancements—including a ReadOnly type for TypedDict, a @warnings.deprecated decorator, the TypeIs construct, is_protocol and get_protocol_members utilities, default TypeVar support with has_default(), the NoDefault sentinel, and several performance and API clean‑ups—providing developers with more expressive and efficient static type checking capabilities.