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.
dataset/ETHPy150Open CollabQ/CollabQ/.google_appengine/google/appengine/ext/db/__init__.py/query_descendants