          f = TestArticleForm({
              'headline': 'New headline',
              'slug': 'new-headline',
              'pub_date': '1988-01-04',
              'writer': six.text_type(w_royko.pk),
              'article': 'Hello.',
              'categories': [six.text_type(c1.id), six.text_type(c2.id)]
          }, instance=new_art)
          new_art = f.save()
          self.assertEqual(new_art.id == art_id_1, True)
 
</s> remove             'categories': [six.text_type(c1.id), six.text_type(c2.id)]
        }, instance=new_art)
 </s> add             'categories': [six.text_type(self.c1.id), six.text_type(self.c2.id)]
        }
        # Create a new article, with categories, via the form.
        f = ArticleForm(form_data) </s> remove         self.assertEqual(new_art.id == art_id_1, True)
        new_art = Article.objects.get(id=art_id_1)
 </s> add         new_art = Article.objects.get(id=new_art.id)
        art_id_1 = new_art.id </s> remove         f = TestArticleForm({'headline': 'New headline', 'slug': 'new-headline', 'pub_date': '1988-01-04',
            'writer': six.text_type(w_royko.pk), 'article': 'Hello.'}, instance=new_art)
 </s> add         form_data['categories'] = []
        f = ArticleForm(form_data, instance=new_art) </s> remove         self.assertEqual(new_art.id == art_id_1, True)
 </s> add         self.assertEqual(new_art.id, art_id_1) </s> remove         # Create a new article, with categories, via the form.
        f = ArticleForm({'headline': 'The walrus was Paul', 'slug': 'walrus-was-paul', 'pub_date': '1967-11-01',
            'writer': six.text_type(w_royko.pk), 'article': 'Test.', 'categories': [six.text_type(c1.id), six.text_type(c2.id)]})
 </s> add         # Create a new article, with no categories, via the form.
        f = ArticleForm(form_data)
            'writer': six.text_type(self.w_royko.pk),
          f = TestArticleForm({
              'headline': 'New headline',
              'slug': 'new-headline',
              'pub_date': '1988-01-04',
            'writer': six.text_type(self.w_royko.pk),
              'article': 'Hello.',
              'categories': [six.text_type(c1.id), six.text_type(c2.id)]
          }, instance=new_art)
          new_art = f.save()
          self.assertEqual(new_art.id == art_id_1, True)
keep keep keep keep replace keep keep keep keep keep
 Fixed #6103 -- Splitted tests in model_forms tests 
tests/model_forms/tests.py