如何在swift 5中设置实例化后可以推送的初始viewController

import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?

    func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        
        // 创建主窗口
        window = UIWindow(frame: UIScreen.main.bounds)
        
        // 创建实例化的ViewController对象
        let initialViewController = YourInitialViewController()
        
        // 将实例化的ViewController对象设置为主窗口的根视图控制器
        window?.rootViewController = initialViewController
        
        // 设置主窗口可见
        window?.makeKeyAndVisible()
        
        return true
    }
}