title: Django ORM returning the same values multiple times when using .distinct()
body: <p>When using <code>.distinct()</code> on a set of objects, the same values are being repeated over and over, which defeats the purpose of using <code>.distinct()</code></p>
  
  <p>An example from a project I'm working on:</p>
  
  <pre><code>In [5]: Section.objects.filter(module=15).values('section').distinct()
  Out[5]: [{'section': '1'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, {'section': '2'}, '...(remaining elements truncated)...']
  </code></pre>
  
  <p>Why is it returning each value instead of only the distinct ones?</p>
  
  <p>For reference, here is my model:</p>
  
  <pre><code>class Section(models.Model):
      module = models.ForeignKey(Module, on_delete=models.CASCADE)
      title = models.CharField(max_length=400)
      section = models.CharField(max_length=3)
      topic = models.CharField(max_length=3)
      subtopic = models.CharField(max_length=3)
      subsubtopic = models.CharField(max_length=3)
      language = models.CharField(max_length=2)
      def __str__(self):
          return self.sectionid() + " - " + self.title
      def sectionid(self):
          return self.module.moduleid + ": " + self.justsectionid()
      def justsectionid(self):
          return self.section + "." + self.topic + "." + self.subtopic + \
          self.subsubtopic + "-" + self.language
      class Meta:
          ordering = ['section', 'topic', 'subtopic', 'subsubtopic', 'language']
  </code></pre>