@abc.abstractmethod<EOL><INDENT>def is_ancestor_of_gradebook(self, id_, gradebook_id):<DEDENT>
return<EOL>
Tests if an ``Id`` is an ancestor of a gradebook.

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

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