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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 quit(self):
 """Shut down the SC2 process."""

    try:
      # Don't expect a response.
      self._client.write(sc_pb.Request(quit=sc_pb.RequestQuit()))
    except protocol.ConnectionError:
      pass  # It's likely already (shutting) down, so continue as if it worked.
    finally:
      self.close()