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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def Send(self, message):
 """Send a message through Fleetspeak. Args: message: A message protocol buffer. Returns: Size of the message in bytes. Raises: ValueError: If message is not a common_pb2.Message. """

    if not isinstance(message, common_pb2.Message):
      raise ValueError("Send requires a fleetspeak.Message")

    if message.destination.service_name == "system":
      raise ValueError(
          "Only predefined messages can have destination.service_name == \"system\"")

    return self._SendImpl(message)