@utilities.arguments_not_none<EOL><INDENT>def is_descendant_of_objective(self, id_, objective_id):<DEDENT>
raise errors.Unimplemented()<EOL>
Tests if an ``Id`` is a descendant of an objective.

        arg:    id (osid.id.Id): an ``Id``
        arg:    objective_id (osid.id.Id): the ``Id`` of an objective
        return: (boolean) - ``true`` if the ``id`` is a descendant of
                the ``objective_id,`` ``false`` otherwise
        raise:  NotFound - ``objective_id`` is not found
        raise:  NullArgument - ``id`` or ``objective_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``.