def get_source_types_by_destination(self, destination_type=None):
raise Unimplemented()<EOL>
Gets all source Types related to the given destination ``Type``.

        arg:    destination_type (osid.type.Type): a destination type
        return: (osid.type.TypeList) - the source types
        raise:  NullArgument - ``destination_type`` is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*