title: Django querysets select average and best result
body: <p>I have a model like this:</p>
  
  <pre><code>class Quiz(models.Model):
      user = models.ForeignKey(User, unique=True)
      school_class = models.CharField(max_length=3, choices=klasa_choices)
      points = models.DecimalField(max_digits=5, decimal_places=2,default=0)
      date = models.DateTimeField(null=True,blank=True)
      active = models.BooleanField(default=False)
  </code></pre>
  
  <p>Basically I'd like to get the average score (points) and the best result with the corresponding user for each school_class . Can this be done easily? (i.e without additional computing?)</p>
  
  <p>So far I've come to:</p>
  
  <pre><code>Quiz.objects.values('school_class').annotate(avg=Avg('points'),max=Max('points')).order_by('-avg')
  </code></pre>
  
  <p>but how do I also get the user with the best score?</p>