func timeObserver() {
 let interval = CMTimeMake(1, 2)
         let timeObserverToken = avPlayer?.addPeriodicTimeObserver(forInterval: interval, queue: DispatchQueue.main) { [weak self] time in
  let seconds = CMTimeGetSeconds(time)
            let secondsTime = Int(seconds.truncatingRemainder(dividingBy: 60.0))

            let MinutesTime =  Int(seconds/60)

            if let duration = self?.avPlayer?.currentItem?.duration {
                    let durationTime = CMTimeGetSeconds(duration)
                     let AllTime = self?.avPlayer?.currentItem?.duration.seconds
                        var min = "0:00"
                         var startTimeHere = "0:00"

               if ((AllTime?.isNaN)!) {
                    print("is nan")
               } else {
                    let durationMin = (Int(AllTime!) % 3600) / 60
                        let durationSec = (Int(AllTime!) % 3600) % 60
                             min = "\(durationMin):\(durationSec)"
                                 startTimeHere = "\(MinutesTime):\(secondsTime)"
                }

                 print("time observ " + String(describing: time))
                 self?.timeDelegate?.changeTimeSlider(time: Float(seconds / durationTime), start: startTimeHere, duration: String(min))

            }
        }
    }