old_contents: 'use strict';
  
  var UltrasonicSensor = require('../index').UltrasonicSensor;
  
  var ultrasonicSensor = new UltrasonicSensor(15, 14);
  
  setInterval(function () {
      console.log(ultrasonicSensor.getDistanceCm());
  }, 60);
  
new_contents: 'use strict';
  
  var UltrasonicSensor = require('../index').UltrasonicSensor;
  
  var ultrasonicSensor = new UltrasonicSensor(15, 14);
  
  setInterval(function () {
      console.log(ultrasonicSensor.getDistanceCm().toFixed(2));
  }, 60);
  
subject: Update test