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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def gen_all_subclasses(cls: Type) -> Generator[Type, None, None]: """ Generates all subclasses of a class. Args: cls: a class Yields: all subclasses """


    for s1 in cls.__subclasses__():
        yield s1
        for s2 in gen_all_subclasses(s1):
            yield s2