@abc.abstractmethod<EOL><INDENT>def get_time_period_search_order(self):<DEDENT>
return<EOL>
Gets a time period search order.

        The ``TimePeriodSearchOrder`` is supplied to a
        ``TimePeriodSearch`` to specify the ordering of results.

        :return: the time period search order
        :rtype: ``osid.calendaring.TimePeriodSearchOrder``


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