title: Return a list of lists to template and render it
body: <p>In my project I deal with various sorts of events taking places in different cities. I'd like to present list of events per city in a template, but how to do that ? My view now looks like this :</p>
  
  <pre><code>def events_by_state(request, state):
      cities = City.objects.filter(state_slug=state)
  </code></pre>
  
  <p>For each city I'd like do a query : </p>
  
  <pre><code>for c in cities:
      events_list = Event.objects.filter(city=c)
  </code></pre>
  
  <p>But then I have problem in what form and how should I send it, as well as use in my template ??</p>