typing — Support for type hints — Python 3.10.1 documentation
docs.python.org › 3 › libraryJan 05, 2022 · These types became redundant in Python 3.9 when the corresponding pre-existing classes were enhanced to support []. The redundant types are deprecated as of Python 3.9 but no deprecation warnings will be issued by the interpreter. It is expected that type checkers will flag the deprecated types when the checked program targets Python 3.9 or newer.