Track the progress of more than one data tasks at the same time in swift

Question

I am downloading a couple of images and want to show the user some kind of progress until its finished. I found a way to track the progress of data tasks from this question get progress from dataTaskWithURL in swift but it only tracks the download progress of one task. I would like to get the progress of all tasks together from the moment the first one starts until the last one has finished downloading.

Tracking the download with this observation I found at the provided link.

private var observation: NSKeyValueObservation?

deinit {
   observation?.invalidate()
}

download all images from an array of links

for Url in URLArray{
     dispatchImages.enter()
     getImage(withURL: URL(string: Url)!){ image in
           dispatchImages.leave(
     }
}

check if the image was already cached before

// MARK: getImage
func getImage(withURL url:URL, completion: @escaping (_ image:UIImage?)->()) {
    if let cachedVersion = cache.object(forKey: url.absoluteString as NSString) {
        print("image was cached before")
        completion(cachedVersion.image)
    } else {
        downloadImage(withURL: url, completion: completion)
    }
}

download the image with a data task

// MARK: downloadImage
func downloadImage(withURL url:URL, completion: @escaping (_ image:UIImage?)->()) {
     let dataTask = URLSession.shared.dataTask(with: url) { data, responseURL, error in
         var downloadedImage:UIImage?
            
         if let error = error{
             print(error)
         }
            
         if let data = data {
             downloadedImage = UIImage(data: data)
         }
         // when url contains an image
         if downloadedImage != nil {
         print("image was downloaded")
         // cache the image
         let cacheImage = ImageCache()
         cacheImage.image = downloadedImage
         self.cache.setObject(cacheImage, forKey: url.absoluteString as NSString)
        }
        DispatchQueue.main.async {
           completion(downloadedImage)
        }
    }
    observation = dataTask.progress.observe(\.fractionCompleted) { progress, _ in
    print("progress: ", progress.fractionCompleted)
    }
    dataTask.resume()
}