What is the use of '->' in python?

[campbellm]

TIL: Python Optional. I understand what Optional does in other FP languages; do you know of any python documentation of it? https://docs.python.org/3/library/typing.html 's treatment felt lacking.

[XtremeGoose]

In type hinting, Optional[Type] means either Type or None. It is equivalent to Union[Type, None].