def get_bank_query(self):
raise errors.Unimplemented()<EOL>
Gets the query for a bank.

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

        return: (osid.assessment.BankQuery) - the bank query
        raise:  Unimplemented - ``supports_bank_query()`` is ``false``
        *compliance: optional -- This method must be implemented if
        ``supports_bank_query()`` is ``true``.*