var audioEngine: AVAudioEngine = AVAudioEngine()
    var audioFilePlayer: AVAudioPlayerNode = AVAudioPlayerNode()

    override func viewDidLoad() {
        super. viewDidLoad()

        guard let filePath: String = Bundle.main.path(forResource: "chimes", ofType: "wav") else{ return }
        print("\(filePath)")
        let fileURL: URL = URL(fileURLWithPath: filePath)
        guard let audioFile = try? AVAudioFile(forReading: fileURL) else{ return }

        let audioFormat = audioFile.processingFormat
        let audioFrameCount = UInt32(audioFile.length)
        guard let audioFileBuffer = AVAudioPCMBuffer(pcmFormat: audioFormat, frameCapacity: audioFrameCount)  else{ return }
        do{
            try audioFile.read(into: audioFileBuffer)
        } catch{
            print("over")
        }
        let mainMixer = audioEngine.mainMixerNode
        audioEngine.attach(audioFilePlayer)
        audioEngine.connect(audioFilePlayer, to:mainMixer, format: audioFileBuffer.format)
        try? audioEngine.start()
        audioFilePlayer.play()
        audioFilePlayer.scheduleBuffer(audioFileBuffer, at: nil, options:AVAudioPlayerNodeBufferOptions.loops)
    }