          self.assertEqual(new_art.id == art_id_1, True)
          new_art = Article.objects.get(id=art_id_1)
          self.assertQuerysetEqual(new_art.categories.all(), [])
  
          # 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)]})
          new_art = f.save()
          art_id_2 = new_art.id
          self.assertEqual(art_id_2 not in (None, art_id_1), True)
          new_art = Article.objects.get(id=art_id_2)
          self.assertQuerysetEqual(new_art.categories.order_by('name'), ["Entertainment", "It's a test"])
 
</s> remove         self.assertEqual(art_id_2 not in (None, art_id_1), True)
 </s> add         self.assertNotIn(art_id_2, (None, art_id_1)) </s> remove         self.assertQuerysetEqual(new_art.categories.order_by('name'), ["Entertainment", "It's a test"])

        # Create a new article, with no 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.'})
        new_art = f.save()
        art_id_3 = new_art.id
        self.assertEqual(art_id_3 not in (None, art_id_1, art_id_2), True)
        new_art = Article.objects.get(id=art_id_3)
 </s> add  </s> remove         self.assertEqual(new_art.id == art_id_1, True)
 </s> add         self.assertEqual(new_art.id, art_id_1) </s> remove         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         form_data['categories'] = [six.text_type(self.c1.id), six.text_type(self.c2.id)]
        f = ArticleForm(form_data) </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)
        # Create a new article, with no categories, via the form.
        f = ArticleForm(form_data)
          self.assertEqual(new_art.id == art_id_1, True)
          new_art = Article.objects.get(id=art_id_1)
          self.assertQuerysetEqual(new_art.categories.all(), [])
  
        # Create a new article, with no categories, via the form.
        f = ArticleForm(form_data)
        # Create a new article, with no categories, via the form.
        f = ArticleForm(form_data)
        # Create a new article, with no categories, via the form.
        f = ArticleForm(form_data)
          new_art = f.save()
          art_id_2 = new_art.id
          self.assertEqual(art_id_2 not in (None, art_id_1), True)
          new_art = Article.objects.get(id=art_id_2)
          self.assertQuerysetEqual(new_art.categories.order_by('name'), ["Entertainment", "It's a test"])
keep keep keep keep replace replace replace keep keep keep keep keep
 Fixed #6103 -- Splitted tests in model_forms tests 
tests/model_forms/tests.py