from typing import Tuple, Union


def inspect_optional_typing(annotation) -> Tuple[bool, type]:
    # seems like at some point internal behavior on typing Union changed
    # https://bugs.launchpad.net/ubuntu/+source/python3.5/+bug/1650202
    if "Union" not in str(annotation):
        return False, type(None)

    if hasattr(annotation, '__origin__'):
        is_union = annotation.__origin__ == Union
    else:
        is_union = issubclass(annotation, Union)

    if not is_union:
        return False, type(None)

    if hasattr(annotation, '__args__'):
        union_params = annotation.__args__
    else:
        union_params = annotation.__union_params__

    is_optional = len(union_params) == 2 and isinstance(None, union_params[1])
    return is_optional, union_params[0]

@@ -247,16 +247,54 @@
  %22Union%22
+ not in str(annotation) and %22Optional%22
  not in 

Fix optional inspection in 3.9