@abc.abstractmethod<EOL><INDENT>def get_commitments_by_record_type(self, commitment_record_type):<DEDENT>
return<EOL>
Gets a ``CommitmentList`` containing the given event commitment record ``Type``.

        :param commitment_record_type: a commitment record type
        :type commitment_record_type: ``osid.type.Type``
        :return: list of commitments
        :rtype: ``osid.calendaring.CommitmentList``
        :raise: ``NullArgument`` -- ``event_record_type`` is ``null``
        :raise: ``OperationFailed`` -- unable to complete request
        :raise: ``PermissionDenied`` -- authorization failure

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