def query_descendants(model_instance):
 result = Query().ancestor(model_instance)
 result.filter((datastore_types.KEY_SPECIAL_PROPERTY + ' >'), model_instance.key())
 return result

def query_descendants ( model_instance ) : result = Query ( ) . ancestor ( model_instance ) result . filter ( ( datastore_types . KEY_SPECIAL_PROPERTY + ' >' ) , model_instance . key ( ) ) return result
returns a query for all the descendants of a model instance .