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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 chat(self, message):
 """Send chat message as a broadcast."""

    if message:
      action_chat = sc_pb.ActionChat(
          channel=sc_pb.ActionChat.Broadcast, message=message)
      action = sc_pb.Action(action_chat=action_chat)
      return self.act(action)