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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 cleanup(self):
 """ Cleanup resources used during execution """

        if self.local_port is not None:
            logger.debug(("Stopping ssh tunnel {0}:{1}:{2} for "
                          "{3}@{4}".format(self.local_port,
                                           self.remote_address,
                                           self.remote_port,
                                           self.username,
                                           self.address)))
            if self.forward is not None:
                self.forward.stop()
                self.forward.join()
            if self.transport is not None:
                self.transport.close()