Templates

They have Django templates:

import os
from google.appengine.ext.webapp import template

import cgi
import wsgiref.handlers

from google.appengine.api import users
from google.appengine.ext import webapp
from google.appengine.ext import db

class Greeting(db.Model):
    author = db.UserProperty()
    content = db.StringProperty(multiline=True)
    date = db.DateTimeProperty(auto_now_add=True)
  
class MainPage(webapp.RequestHandler):
  def get(self):
    greetings = Greeting.all().order('-date')

    if users.get_current_user():
      url = users.create_logout_url(self.request.uri)
      url_linktext = 'Logout'
    else:
      url = users.create_login_url(self.request.uri)
      url_linktext = 'Login'

    template_values = {
      'greetings': greetings,
      'url': url,
      'url_linktext': url_linktext,
      }

    path = os.path.join(os.path.dirname(__file__), 'index.html')
    self.response.out.write(template.render(path, template_values))

class Guestbook(webapp.RequestHandler):
    def post(self):
        greeting = Greeting()
    
        if users.get_current_user():
            greeting.author = users.get_current_user()

        greeting.content = self.request.get('content')
        greeting.put()
        self.redirect('/')

def main():
  application = webapp.WSGIApplication(
                                       [('/', MainPage),
                                        ('/sign', Guestbook)],
                                       debug=True)
  wsgiref.handlers.CGIHandler().run(application)

if __name__ == "__main__":
  main()

<html>
  <body>
    {% for greeting in greetings %}
      {% if greeting.author %}
        <b>{{ greeting.author.nickname }}</b> wrote:
      {% else %}
       An anonymous person wrote:
      {% endif %}
      <blockquote>{{ greeting.content|escape }}</blockquote>
    {% endfor %}

    <form action="/sign" method="post">
      <div><textarea name="content" rows="3" cols="60"></textarea></div>
      <div><input type="submit" value="Sign Guestbook"></div>
    </form>

    <a href="{{ url }}">{{ url_linktext }}</a>

  </body>
</html>