@abc.abstractmethod<EOL><INDENT>def is_descendant_of_agency(self, id_, agency_id):<DEDENT>
return<EOL>
Tests if an ``Id`` is a descendant of an agency.

        :param id: an ``Id``
        :type id: ``osid.id.Id``
        :param agency_id: the ``Id`` of an agency
        :type agency_id: ``osid.id.Id``
        :return: ``true`` if the ``id`` is a descendant of the ``agency_id,``  ``false`` otherwise
        :rtype: ``boolean``
        :raise: ``NotFound`` -- ``agency_id`` is not found
        :raise: ``NullArgument`` -- ``agency_id`` or ``id`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure

        *compliance: mandatory -- This method must be implemented.*
        *implementation notes*: If ``id`` is not found return ``false``.