@abc.abstractmethod<EOL><INDENT>def get_calendar_ids_by_time_period(self, time_period_id):<DEDENT>
return<EOL>
Gets the list of ``Calendar Ids`` mapped to a ``TimePeriod``.

        :param time_period_id: ``Id`` of a ``TimePeriod``
        :type time_period_id: ``osid.id.Id``
        :return: list of calendar ``Ids``
        :rtype: ``osid.id.IdList``
        :raise: ``NotFound`` -- ``time_period_id`` is not found
        :raise: ``NullArgument`` -- ``time_period_id`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure

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