         }
     }
     
-    private func findScreenshot() {
+    fileprivate func findScreenshot() {
         guard let screenshot = PHAsset.fetchLastScreenshot() else { fail(with: .fetchFailure); return }
         
         // Fall back to the `.default()` image manager if an image manager wasn’t set on initialization.

            OperationQueue.main.addOperation {
                switch authorizationStatus {
                case .authorized:
                    self.findScreenshot()
                case .denied, .notDetermined, .restricted:
                    self.fail(with: .unauthorized(status: authorizationStatus))
                }

     - parameter notificationCenter: A notification center that will listen for screenshot notifications.
     - parameter application:        An application that will be the `object` of the notification observer.
     - parameter imageManager:       An image manager used to fetch the image data of the screenshot. If `nil`, the `default()` image manager will be used.
     - parameter photoLibrary:       The photo library used for detecting a change event after a screenshot is taken. Defaults to `.shared()`.
     */
    public init(delegate: ScreenshotDetectorDelegate, notificationCenter: NotificationCenter = .default, application: UIApplication = .shared, imageManager: PHImageManager? = nil, photoLibrary: PHPhotoLibrary = .shared()) {
        self.delegate = delegate
        self.notificationCenter = notificationCenter
        self.application = application
        self.imageManager = imageManager
        self.photoLibrary = photoLibrary
        
        super.init()
        
