title: Ambiguous reference to member 'subscript'
body: <p>Here is my Swift 2 code:</p>
  
  <pre><code>func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -&gt; UITableViewCell {
      var cell: UITableViewCell!
      cell = tableView.dequeueReusableCellwithIdentifier: forWithIdentifier("idCellChannel", forIndexPath: indexPath as IndexPath)
  
      let channelTitleLabel = cell.viewWithTag(10) as! UILabel
      let thumbnailImageView = cell.viewWithTag(12) as! UIImageView
  
      let channelDetails = channelsDataArray[indexPath.row]
      channelTitleLabel.text = channelDetails["title"] as? String
  
      // Error  Ambiguous reference to member 'subscript'
      thumbnailImageView.image = UIImage(data: NSData(contentsOfURL: NSURL(string: (channelDetails["thumbnail"] as? String)!)!)!)
  
      return cell
  }
  </code></pre>
  
  <p>Please give me a solution for Swift 3.</p>