ret_type.py

from typing import Type, Union


class BaseType:
    pass

class EvenType:
    pass

class OddType:
    pass


def func(num: Union[int, str], return_type_spec: Type[BaseType]) -> BaseType:
    try:
        if num % 2 == 0:
            return EvenType()
    
        return OddType()
    
    except TypeError:
        return BaseType()