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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 close_stream_transport(self, stream_transport, timeout):
 """Remove the given stream transport's id from our map of id's. If the stream id is actually removed, we send a CLSE message to let the remote end know (this happens when we are ack'ing a CLSE message we received). The ADB protocol doesn't say this is a requirement, but ADB does it, so we do too. Args: stream_transport: The stream transport to close. timeout: Timeout on the operation. Returns: True if the id was removed and message sent, False if it was already missing from the stream map (already closed). """

    with self._stream_transport_map_lock:
      if stream_transport.local_id in self._stream_transport_map:
        del self._stream_transport_map[stream_transport.local_id]
        # If we never got a remote_id, there's no CLSE message to send.
        if stream_transport.remote_id:
          self.transport.write_message(adb_message.AdbMessage(
              'CLSE', stream_transport.local_id, stream_transport.remote_id),
                                       timeout)
        return True
    return False