code: func GetArticle(w http.ResponseWriter, r *http.Request) {
  	// Assume if we've reach this far, we can access the article
  	// context because this handler is a child of the ArticleCtx
  	// middleware. The worst case, the recoverer middleware will save us.
  	article := r.Context().Value("article").(*Article)
  
  	if err := render.Render(w, r, NewArticleResponse(article)); err != nil {
  		render.Render(w, r, ErrRender(err))
  		return
  	}
  }
docs: // GetArticle returns the specific Article. You'll notice it just
  // fetches the Article right off the context, as its understood that
  // if we made it this far, the Article must be on the context. In case
  // its not due to a bug, then it will panic, and our Recoverer will save us.