title: How to get time difference in hours between two dates (Django)
body: <p>I am trying to subtract two dates stored in a database to get difference in hours.
  However these values are in query sets, so I am unable to subtract them.</p>
  
  <p>For example:</p>
  
  <pre><code>date1 = table.objects.values_list('field1').filter(id=1))
  date2 = table.objects.values_list('field1').filter(id=2))
  timediff = date1-date2
  </code></pre>
  
  <p>How to do this?</p>