如何手动设置AVPlayerViewController的开始和结束时间

import AVKit

// 创建AVPlayer对象
let videoURL = URL(string: "https://example.com/video.mp4")
let player = AVPlayer(url: videoURL!)

// 创建AVPlayerViewController对象
let playerViewController = AVPlayerViewController()
playerViewController.player = player

// 设置开始和结束时间
let startTime = CMTime(seconds: 10, preferredTimescale: 1)
let endTime = CMTime(seconds: 30, preferredTimescale: 1)
player.seek(to: startTime)

// 监听播放状态
player.addPeriodicTimeObserver(forInterval: CMTime(seconds: 1, preferredTimescale: 1), queue: DispatchQueue.main) { time in
    if time >= endTime {
        player.pause()
    }
}

// 显示AVPlayerViewController
present(playerViewController, animated: true, completion: nil)