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

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