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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 loseConnection(self):
 """ Close the connection and terminate the exiftool process. @rtype: C{Deferred} @return: A deferred whose callback will be invoked when the connection was closed. """

        if self._stopped:
            result = self._stopped
        elif self.connected:
            result = defer.Deferred()
            self._stopped = result
            self.transport.write(b'\n'.join((b'-stay_open', b'False', b'')))
        else:
            # Already disconnected.
            result = defer.succeed(self)

        return result