title: formset delete inline instance
body: <p>Have identified the object that i need to delete from the formset.</p>
  
  <pre><code>def save_formset(self, request, form, formset, change):
          instances = formset.save(commit=False)
          for instance in instances:
              ......
          if formset.deleted_forms:
              for obj in formset.deleted_forms:
                 obj.delete() //here is the issue
  </code></pre>
  
  <p>it ends with the error </p>
  
  <pre><code>*** AttributeError: 'ActivitiesForm' object has no attribute 'delete'
  </code></pre>
  
  <p>This is what formset.deleted_forms is</p>
  
  <pre><code>(Pdb) formset.deleted_forms
  [&lt;django.forms.widgets.ActivitiesForm object at 0x7f19f6435f50&gt;]
  </code></pre>
  
  <p>What went wrong here? Basically i m trying to delete inline entry choosen from admin</p>