function createAssemblyLine() {

  return {
    hasClima: (car) => {
      car.temp = 21;
      car.tempSettings = 21;
      car.adjustTemp = () => {
        if (car.temp < car.tempSettings) {
          car.temp++;
        } else if (car.temp > car.tempSettings) {
          car.temp--;
        }

      };
    },
    hasAudio: (car) => {
      car.currentTrack = {'name': '', 'artist': ''};
      car.nowPlaying = () => {
        if (car.currentTrack !== null) {
          console.log(`Now playing '${car.currentTrack.name}' by ${car.currentTrack.artist}`);
        }
      };
    },
    hasParktronic: (car) => {
      car.checkDistance = (distance) => {
        if (distance < 0.1) {
          console.log('Beep! Beep! Beep!');
        } else if (distance >= 0.1 && distance < 0.25) {
          console.log('Beep! Beep!');
        } else if (distance >= 0.25 && distance < 0.5) {
          console.log('Beep!');
        } else {
          console.log('');
        }
      };
    }
  };
}