title: Error encountered when generating numbers in series
body: <p>In every post that will be posted by user, I want number to be generated from Integer field in series. I have encountered the error named "TypeError: unsupported operand type(s) for +: 'dict' and 'int'"</p>
  
  <p>How would I get rid off this error?</p>
  
  <p>views.py</p>
  
  <pre><code> @login_required
  def Claim(request):
      max_val = Documents.objects.all().aggregate(Max('pay_no'))
  
      # then just make new object, and assign max+1 to 'that_field_in_question'
      control_number = Documents(pay_no=max_val + 1)
      control_number.save()
  
      return render(request,"loststuffapp/claim.html",context={"documents":Documents.objects.all()})
  </code></pre>