def get_updated_value_for_datastore(self, model_instance):
    if self.auto_now:
      return _time_to_datetime(self.now())
    return AUTO_UPDATE_UNCHANGED
Get new value for property to send to datastore.
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/db/__init__.py/TimeProperty.get_updated_value_for_datastore