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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 duty_cycle_sp(self):
 """ Writing sets the duty cycle setpoint. Reading returns the current value. Units are in percent. Valid values are -100 to 100. A negative value causes the motor to rotate in reverse. """

        self._duty_cycle_sp, value = self.get_attr_int(self._duty_cycle_sp, 'duty_cycle_sp')
        return value