Swift 2 and Xcode 7 and ge this error

Import Foundation


class NetworkOperation {

    lazy var config: NSURLSessionConfiguration = NSURLSessionConfiguration.defaultSessionConfiguration()
    lazy var session: NSURLSession = NSURLSession(configuration: self.config)
    let queryURL: NSURL

    typealias JSONDictionaryCompletion = ([String: AnyObject]?) -> Void

    init(url: NSURL) {
        self.queryURL = url
    }


    func downloadJSONFromURL(completion: JSONDictionaryCompletion ) {

        let request: NSURLRequest = NSURLRequest(URL: queryURL)
        let dataTask = session.dataTaskWithRequest(request) { (let data, let response, let error) in

            // 1. Check HTTP response for successfull GET Request

            if let httpResponse = response as? NSHTTPURLResponse {

                switch (httpResponse.statusCode) {
                case 200:
                     // 2. Create JSON object with the data
                    let jsonDictionary = try NSJSONSerialization.JSONObjectWithData(data, options: []) as? [String: AnyObject]
                    completion(jsonDictionary)
                default:
                    print("GET Request not successful. HTTP status Code: \(httpResponse)")
                }

            } else {
                print("Error: Not a Valid HTTP Response")
            }



        }

        dataTask!.resume()

    }


}