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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 validate_permission(self, key, permission):
 """ validates if group can get assigned with permission"""

        if permission.perm_name not in self.__possible_permissions__:
            raise AssertionError(
                "perm_name is not one of {}".format(self.__possible_permissions__)
            )
        return permission