Not able to debug notificaton content extension in ios 10 notification

print statement does not work inside notification content extension, although I am able to modify the Label text and other fields, below is my code

class NotificationViewController: UIViewController, UNNotificationContentExtension {    @IBOutlet weak var label: UILabel!    override func viewDidLoad() {        super.viewDidLoad()        print("inside viewDidLoad of notificationViewController")    }    func didReceive(_ notification: UNNotification) {        self.label?.text = notification.request.content.body        print("inside didReceive of notificationViewController")    }}