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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, steering, speed):
 """ Start rotating the motors according to the provided ``steering`` and ``speed`` forever. """

        (left_speed, right_speed) = self.get_speed_steering(steering, speed)
        MoveTank.on(self, SpeedNativeUnits(left_speed), SpeedNativeUnits(right_speed))