swift how change the preview image of url code example

Example: display image from url swift

let imageCache = NSCache<AnyObject, AnyObject>()

extension UIImageView {
    func setImage(from url: URL, contentMode mode: UIViewContentMode = .scaleAspectFit) {
        contentMode = mode
        
        if let imageFromCache = imageCache.object(forKey: url as AnyObject) {
            self.image = imageFromCache as? UIImage
            return
        }
        
        URLSession.shared.dataTask(with: url) { data, response, error in
            guard
                let httpURLResponse = response as? HTTPURLResponse, httpURLResponse.statusCode == 200,
                let mimeType = response?.mimeType, mimeType.hasPrefix("image"),
                let data = data, error == nil,
                let imageToCache = UIImage(data: data)
                else { return }
            DispatchQueue.main.async() {
                imageCache.setObject(imageToCache, forKey: url as AnyObject)
                self.image = imageToCache
            }
        }.resume()
    }
    func setImage(from link: String, contentMode mode: UIViewContentMode = .scaleAspectFit) {
        guard let url = URL(string: link) else { return }
        setImage(from: url, contentMode: mode)
    }
}