if let url = NSURL(string: "https://upload.wikimedia.org/wikipedia/en/thumb/7/7d/Full_Sail_University.svg/1280px-Full_Sail_University.svg.png") {

        let task = session.dataTask(with: url, completionHandler: { (data, response, error) in
            // check against error
            if let error = error {
                print("Data task failed with error: (error)")
                return
            }

            print("Success")

        })
        task.resume()
    }

if let url = NSURL(string: "https://upload.wikimedia.org/wikipedia/en/thumb/7/7d/Full_Sail_University.svg/1280px-Full_Sail_University.svg.png")

if let url = URL(string: "https://upload.wikimedia.org/wikipedia/en/thumb/7/7d/Full_Sail_University.svg/1280px-Full_Sail_University.svg.png") {