_map_attributes_implementing_interface
function _map_attributes_implementing_interface(instance: instance, instance_map: map<text, gtv?>, options: list<option>, children_mappers: list<(instance, map<text, gtv?>, list<option>) -> unit>, interfaces: list<dclass>, mapper: (map<text, gtv?>, map<key_name, gtv?>, list<option>) -> unit, meta: list<meta>?)