Twitter View not showing in iOS

ios
swift
#1

I am testing out Fabric for iOS.

I have added the Twitter post like so:

import UIKit
import TwitterKit

class ComponentViewController: UIViewController {
  override func viewDidLoad() {
    super.viewDidLoad()
    Twitter.sharedInstance().logInGuestWithCompletion { (session, error) in
        Twitter.sharedInstance().APIClient.loadTweetWithID("20") { (tweet, error) in
            self.view.addSubview(TWTRTweetView(tweet: tweet))
       }
    }
  }
}

However it does not show on the View.

#2