def get_statistic_query(self):
raise Unimplemented()<EOL>
Gets the query for a statistic.

        Multiple retrievals produce a nested ``OR`` term.

        return: (osid.metering.StatisticQuery) - the statistic query
        raise:  Unimplemented - ``supports_statistic_query()`` is
                ``false``
        *compliance: optional -- This method must be implemented if
        ``supports_statistic_query()`` is ``true``.*