override func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
    let vc = storyboard?.instantiateViewController(withIdentifier: "twoVC") as? twoVC

    self.navigationController?.pushViewController(vc!, animated: true)
 //Thread 1: Fatal error: Unexpectedly found nil while unwrapping an Optional value

}


}

class twoVC : UIViewController {
@IBOutlet var label : UILabel!

@IBOutlet var photo : UIImageView!



}