crash

 override func viewDidLoad() {
        super.viewDidLoad()
        var collectionViewFlowLayout = UICollectionViewFlowLayout()
        
        twitterCardCollectionView = UICollectionView(frame:CGRectMake(0, 0, self.view.frame.size.width,self.view.frame.size.height), collectionViewLayout: collectionViewFlowLayout)
        twitterCardCollectionView.registerClass(MultipleCardCollectionViewCell.self, forCellWithReuseIdentifier: "account")
        twitterCardCollectionView.delegate = self
        twitterCardCollectionView.dataSource = self
        twitterCardCollectionView.backgroundColor = UIColor.clearColor()
        self.view.addSubview(twitterCardCollectionView)
        
    }
    
    // Crash appears exactly here
    func collectionView(collectionView: UICollectionView, cellForItemAtIndexPath indexPath: NSIndexPath) -> UICollectionViewCell {
        let cell = collectionView.dequeueReusableCellWithReuseIdentifier("account", forIndexPath: indexPath) as MultipleCardCollectionViewCell
        //A lot of configuration after 
        return cell
    }