How to convert an Objective-C Block into a Swift Closure?

I have the following Objective-C block assignment example from Github dzenbot/DZNPhotoPickerController that I am struggling to convert to Swift. Controller is a UIImagePickerController. controller.finalizationBlock = ^(UIImagePickerController *picker, NSDictionary *info) { UIImage *image = info[UIImagePickerControllerEditedImage]; weakSelf.imageView.image = image; // Dismiss when the crop mode was disabled if (picker.cropMode == DZNPhotoEditorViewControllerCropModeNone) { [weakSelf dismissController:picker]; } }; I have tried the following, but cannot figure out where I am going wrong. controller.finalizationBlock = { (picker: UIImagePickerController, info: NSDictionary) -> UIImagePickerControllerFinalizationBlock! in var image = UIImagePickerControllerEditedImage(info) imageView.image = image // Dismiss when the crop mode was disabled if (picker.cropMode == .None) { dismissEditor(picker) } } The error I get is: "Cannot assign value of type '(UIImagePickerController, NSDictionary) -> UIImagePickerControllerFinalizationBlock!' to type 'UIImagePickerControllerFinalizationBlock!'