Как сделать анимацию перехода между ViewController в Swift?

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import UIKit

class CustomTransitionAnimator: NSObject, UIViewControllerAnimatedTransitioning {
    let duration = 0.5

    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return duration
    }

    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        guard let fromView = transitionContext.view(forKey: .from),
              let toView = transitionContext.view(forKey: .to) else {
            return
        }
        
        let containerView = transitionContext.containerView
        containerView.addSubview(toView)

        toView.alpha = 0.0
        UIView.animate(withDuration: duration, animations: {
            toView.alpha = 1.0
            fromView.alpha = 0.0
        }) { finished in
            fromView.alpha = 1.0
            transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
        }
    }
}

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class FirstViewController: UIViewController, UIViewControllerTransitioningDelegate {
    override func viewDidLoad() {
        super.viewDidLoad()
    }

    @IBAction func presentSecondViewController() {
        let secondViewController = SecondViewController()
        secondViewController.transitioningDelegate = self
        secondViewController.modalPresentationStyle = .fullScreen
        self.present(secondViewController, animated: true, completion: nil)
    }

    // MARK: - UIViewControllerTransitioningDelegate

    func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
        return CustomTransitionAnimator()
    }

    func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
        return CustomTransitionAnimator()
    }
}

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class SecondViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .white

        let dismissButton = UIButton(type: .system)
        dismissButton.setTitle("Dismiss", for: .normal)
        dismissButton.addTarget(self, action: #selector(dismissVC), for: .touchUpInside)

        dismissButton.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(dismissButton)
        NSLayoutConstraint.activate([
            dismissButton.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            dismissButton.centerYAnchor.constraint(equalTo: view.centerYAnchor)
        ])
    }

    @objc func dismissVC() {
        self.dismiss(animated: true, completion: nil)
    }
}