title: Django template filter keeps giving "unsupported operand type"
body: <p>I keep getting this error with my template filter: 
  "unsupported operand type(s) for -: 'datetime.datetime' and 'datetime.date'" I've looked at many other answers dealing with this error but I can't seem to find what's wrong. Any pointers much appreciated.</p>
  
  <p>This is my template filter:</p>
  
  <pre><code>@register.filter(name='get_due_date_string')
  def get_due_date_string(value):
      delta = value - date.today()
  
      if delta.days == 0:
          return "Today!"
      elif delta.days &lt; 1:
          return "%s %s ago!" % (abs(delta.days),
              ("day" if abs(delta.days) == 1 else "days"))
      elif delta.days == 1:
          return "Tomorrow"
      elif delta.days &gt; 1:
          return "In %s days" % delta.days
  </code></pre>