def UpdateFromKey(self, key):
    self._key = key
    entity = self._key.get()
    if entity is not None:
      self._CopyFromEntity(entity)
      self._from_datastore = True
Attempts to get current entity for key and update the unset properties.
dataset/ETHPy150Open GoogleDeveloperExperts/experts-app-backend/endpoints_proto_datastore/ndb/model.py/EndpointsModel.UpdateFromKey