code: func End(nextSlide func()) (title string, content tview.Primitive) {
  	textView := tview.NewTextView().SetDoneFunc(func(key tcell.Key) {
  		nextSlide()
  	})
  	url := "https://github.com/rivo/tview"
  	fmt.Fprint(textView, url)
  	return "End", Center(len(url), 1, textView)
  }
docs: // End shows the final slide.