Не уверен, если вы ищете что-то подобное.
import sys
import typing
foo: typing.List[int] = []
foo_one: typing.Tuple[float] = ()
def _get_type_of_item(param):
"""
typing.get_type_hints(obj[, globals[, locals]]):
Return a dictionary containing type hints for a function, method, module or class object.
"""
return typing.get_type_hints(sys.modules[__name__])[param].__args__
print(_get_type_of_item('foo')) # this will print (<class 'int'>,)
print(_get_type_of_item('foo_one')) # this will print (<class 'float'>,)