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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 stop(self):
        '''stop nsh input'''
        self.mpstate.rl.set_prompt(self.status.flightmode + "> ")
        self.mpstate.functions.input_handler = None
        self.started = False
        # unlock the port
        mav = self.master.mav
        mav.serial_control_send(self.serial_settings.port,
                                0,
                                0, self.serial_settings.baudrate,
                                0, [0]*70)