To make this code clearer:

    def get_users(f) -> Tuple[List, List]:
       return (logged_in_users(f), logged_out_users(f))

    def user_count(f) -> int:
       return len(get_users())

Now it's clear this is just wrong code. To fix it:

    def get_users(f) -> List:
       return logged_in_users(f) + logged_out_users(f)

    def user_count(f) -> int:
       return len(get_users())