@utilities.arguments_not_none<EOL><INDENT>def get_families_by_record_type(self, family_record_type):<DEDENT>
raise errors.Unimplemented()<EOL>
Gets a ``FamilyList`` containing the given family record ``Type``.

        In plenary mode, the returned list contains all known families
        or an error results. Otherwise, the returned list may contain
        only those families that are accessible through this session.

        arg:    family_record_type (osid.type.Type): a family record
                type
        return: (osid.relationship.FamilyList) - the returned ``Family
                list``
        raise:  NullArgument - ``family_record_type`` is ``null``
        raise:  OperationFailed - unable to complete request
        raise:  PermissionDenied - authorization failure
        *compliance: mandatory -- This method must be implemented.*