@abc.abstractmethod<EOL><INDENT>def get_depots_by_parent_genus_type(self, depot_genus_type):<DEDENT>
return<EOL>
Gets a ``DepotList`` corresponding to the given depot genus ``Type`` and include any additional depots with
        genus types derived from the specified ``Type``.

        In plenary mode, the returned list contains all known depots or
        an error results. Otherwise, the returned list may contain only
        those depots that are accessible through this session.

        :param depot_genus_type: a depot genus type
        :type depot_genus_type: ``osid.type.Type``
        :return: the returned ``Depot`` list
        :rtype: ``osid.installation.DepotList``
        :raise: ``NullArgument`` -- ``depot_genus_type`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure

        *compliance: mandatory -- This method must be implemented.*