title: Django-piston: How can I get app_label + model_name?
body: <p>Before I was just using the build-in django serializers and it added a model field.</p>
  
  <pre><code>{
      pk: 1
      model: "zoo.cat"
  }
  </code></pre>
  
  <p>How can I get the same model field using django-piston?</p>
  
  <p>I tried fields = ('id', 'model') but that didn't work.</p>