old_contents: #
  # Handles GET /guestbook -- returns a list of items in the guestbook
  # with a form to add more.
  #
  
  from flask import current_app, escape
  import redis
  
  # Connect to redis.  This is run only when this file is loaded; as
  # long as the pod is alive, the connection is reused.
  redisConnection = redis.StrictRedis(host='redis.guestbook', port=6379, db=0)
  
  def main():
      messages = redisConnection.lrange('guestbook', 0, -1)
  
      items = [("<li>%s</li>" % escape(m.decode('utf-8'))) for m in messages]
      ul = "<ul>%s</ul>" % "\n".join(items)
      return """
        <html><body>
            <h1>Guestbook</h1>      
            <form action="/guestbook" method="POST">
              <input type="text" name="text">
              <button type="submit">Add</button>
            </form>
            <hr/>
            %s
        </body></html>
        """ % ul
  
new_contents: #
  # Handles GET /guestbook -- returns a list of items in the guestbook
  # with a form to add more.
  #
  
  from flask import current_app, escape
  import redis
  
  # Connect to redis.  This is run only when this file is loaded; as
  # long as the pod is alive, the connection is reused.
  redisConnection = redis.StrictRedis(host='redis.guestbook', port=6379, db=0)
  
  def main():
      messages = redisConnection.lrange('guestbook', 0, -1)
  
      items = [("<li>%s</li>" % escape(m.decode('utf-8'))) for m in messages]
      ul = "<ul>%s</ul>" % "\n".join(items)
      return """
        <html><body style="font-family:sans-serif;font-size:2rem;padding:40px">
            <h1>Guestbook</h1>      
            <form action="/guestbook" method="POST">
              <input type="text" name="text">
              <button type="submit">Add</button>
            </form>
            <hr/>
            %s
        </body></html>
        """ % ul
  
subject: update guestbook example css