@abc.abstractmethod<EOL><INDENT>def get_commitments_by_genus_type(self, commitment_genus_type):<DEDENT>
return<EOL>
Gets the commitments for the given event genus type.

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

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