Currently get_args doesn't work for PEP 604 Union:

>>> get_args(int | str)

or new Callables with PEP 612:

>>> P = ParamSpec('P)
>>> get_args(Callable[P, int])
([~P], <class 'int'>)

get_origin doesn't work with PEP 604 Unions:

>>> get_origin(int | str)


PS: the fix has to be backported partly to 3.9. Because get_args doesn't handle collections.abc.Callable either.