如何将UILabel和UIImage放入类方法中

import UIKit

class UIHelper {
    class func createLabel() -> UILabel {
        let label = UILabel()
        label.text = "Hello, World!"
        label.textColor = .black
        label.textAlignment = .center
        label.font = UIFont.systemFont(ofSize: 20)
        return label
    }
    
    class func createImage(named name: String) -> UIImage? {
        return UIImage(named: name)
    }
}

import UIKit

class ViewController: UIViewController {
    override func viewDidLoad() {
        super.viewDidLoad()
        
        // 创建并添加UILabel
        let label = UIHelper.createLabel()
        label.frame = CGRect(x: 20, y: 100, width: view.bounds.width - 40, height: 50)
        view.addSubview(label)
        
        // 创建并添加UIImage
        if let image = UIHelper.createImage(named: "exampleImage") {
            let imageView = UIImageView(image: image)
            imageView.frame = CGRect(x: 20, y: 200, width: 100, height: 100)
            view.addSubview(imageView)
        }
    }
}