def value_from_message(self, message):
    if not isinstance(message, self.message_type):
      raise DecodeError('Expected type %s, got %s: %r' %
                        (self.message_type.__name__,
                         type(message).__name__,
                         message))
    return message
Convert a message to a value instance.
dataset/ETHPy150Open AppScale/appscale/AppServer/lib/protorpc/protorpc/messages.py/MessageField.value_from_message