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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 _get_all_decendents(self, cls):
 """Get all decendents for a given class"""

        decendents = {}
        for sc in cls.__sub_classes__:
            decendents[sc.__name__] = sc
            decendents.update(self._get_all_decendents(sc))
        return decendents