title: Evaluating a Django Query : Using python's .index() on a Django Query [values_list(Flat=True)]
body: <p>I'm trying to figure out what is the rank of a django model object within objects that meet the same criterias.</p>
  
  <p>My idea was to get a flat values_list of primary keys like this:</p>
  
  <p>[In the models.py page, in the Model "Risk", other linked models are Worktask and Type]</p>
  
  <pre><code>my_list_of_filtered_pks = Risk.objects.filter(
          worktask__code = self.worktask.code,
          type__id = self.type.id
      ).values_list('pk', flat=True).order_by('pk')
  </code></pre>
  
  <p>And then get the index of my particular instance using something like:</p>
  
  <pre><code>rank = my_list_of_filtered_pks.index(self.pk)
  </code></pre>
  
  <p>But i get an error saying that my my_list_of_filtered_pks has no attribute 'index'</p>
  
  <pre><code>'QuerySet' object has no attribute 'index'
  </code></pre>
  
  <p>What am i missing here ?</p>
  
  <p>Thanks ! i'm relatively new to django .. !</p>