我在这里得到这个错误：

image.load(url: product?.productImage!)

图像的定义：

@IBOutlet var image: CellImageView!

下面是我的CellImageView类：

import UIKit

class CellImageView: UIImageView {
    var task: URLSessionDataTask!
    var imageCache = NSCache<AnyObject, AnyObject>()

    func load(url: String) {
        let real_url = url.replacingOccurrences(of: *image_path_here*, with: *image_path_here*)
        let imageUrl = URL(string: real_url)
        image = nil

        if let task = task {
            task.cancel()
        }

        if let imageFromCache = imageCache.object(forKey: imageUrl?.absoluteString as AnyObject) as? UIImage {
            image = imageFromCache
        }

        task = URLSession.shared.dataTask(with: imageUrl!, completionHandler: { data, _, error in
            guard let data = data, let newImage = UIImage(data: data) else {
                print(error)
                return
            }
            self.imageCache.setObject(newImage, forKey: imageUrl?.absoluteString as AnyObject)
            DispatchQueue.main.async {
                self.image = newImage
            }
        })
        task.resume()
    }
}

我不知道为什么这给我一个错误。有人能帮助我吗？