code: func (r *Adaptor) DigitalPin(pin string, dir string) (sysfsPin sysfs.DigitalPinner, err error) {
  	i, err := r.translatePin(pin)
  
  	if err != nil {
  		return
  	}
  
  	currentPin, err := r.getExportedDigitalPin(i, dir)
  
  	if err != nil {
  		return
  	}
  
  	if err = currentPin.Direction(dir); err != nil {
  		return
  	}
  
  	return currentPin, nil
  }
docs: // DigitalPin returns matched digitalPin for specified values