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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 on(self, left_speed, right_speed):
 """ Start rotating the motors according to ``left_speed`` and ``right_speed`` forever. Speeds can be percentages or any SpeedValue implementation. """

        (left_speed_native_units, right_speed_native_units) = self._unpack_speeds_to_native_units(left_speed, right_speed)

        # Set all parameters
        self.left_motor.speed_sp = int(round(left_speed_native_units))
        self.right_motor.speed_sp = int(round(right_speed_native_units))

        # This debug involves disk I/O to pull speed_sp so only uncomment
        # if you need to troubleshoot in more detail.
        # log.debug("%s: on at left-speed %s, right-speed %s" %
        #     (self, self.left_motor.speed_sp, self.right_motor.speed_sp))

        # Start the motors
        self.left_motor.run_forever()
        self.right_motor.run_forever()