title: Does Django queryset values_list return a list object?
body: <p>I have a Django app where users post photos, and other leave comments under the photos. </p>
  
  <p>When a comment is left, I need to notify:</p>
  
  <ol>
  <li>Everyone else who wrote in this thread</li>
  <li>The owner of the photo, in case they're not included in (1)</li>
  </ol>
  
  <p>For (1), I do: </p>
  
  <pre><code>#I slice by 25 because I arbitrarily deem anyone beyond that irrelevant. 
  all_commenter_ids = PhotoComment.objects.filter(which_photo=which_photo).order_by('-id').values_list('submitted_by', flat=True)[:25]
  </code></pre>
  
  <p>Next, for (2), I try:</p>
  
  <pre><code>all_relevant_ids = all_commenter_ids.append(which_photo.owner_id)
  all_relevant_ids = list(set(all_relevant_ids))
  </code></pre>
  
  <p>I end up with an error:</p>
  
  <blockquote>
    <p>'ValuesListQuerySet' object has no attribute 'append'</p>
  </blockquote>
  
  <p>I find this strange, because I'm extracting a <strong>values_list</strong>. </p>
  
  <p>Isn't that a list object, and in that case, shouldn't the attribute <code>append</code> work in this scenario? Please explain what's wrong, and suggest alternatives.</p>