func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {

          let cellIndentifier = "cell"

          let cell = collectionView.dequeueReusableCell(withReuseIdentifier: cellIndentifier, for: indexPath) as! ImageCollectionViewCell

          // Supposed fix for scrolling performance issues
          // on iOS collectionView
          cell.layer.shouldRasterize = true
          cell.layer.rasterizationScale = UIScreen.main.scale

          let image = self.images[indexPath.row]

          // Load the image
          let url = URL(string: image.urls.small)
          let data = try? Data(contentsOf: url!)
          cell.imageView.image = UIImage(data: data!)

          return cell
     }