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 AppScale/appscale/AppServer/google/appengine/ext/db/__init__.py/query_descendants