text: #ifndef USSensor_h
  
  #include <Arduino.h>
  #define USSensor_h
  
  class USSensor{
    private:
      byte _trig_pin;
      byte _echo_pin;
      long _duration, _distance;
    public:
      USSensor(byte _trig_pin, byte _echo_pin);
      long calculate_distance();
  };
  
  #endif
  