title: Django and Aggregate: Sum of distinct values?
body: <p>I am trying to do a django aggregate function, but am unable to produce the desired result.</p>
  
  <p>What I've got:</p>
  
  <pre><code>income_posts.values_list('category__name','amount')
  [(u'Donation', Decimal("2000.00")), (u'Paycheck', Decimal("1200.00")), (u'Donation', Decimal("1000.00"))]
  </code></pre>
  
  <p>Desired result:</p>
  
  <pre><code>[(u'Donation', Decimal("3000.00")), (u'Paycheck', Decimal("1200.00))]
  </code></pre>
  
  <p>I need to Sum the 'amount' fields that have the same category__name.</p>