new_contents: from unittest import skipIf, skipUnless
  
  import six
  from django.test import SimpleTestCase
  from django_extensions.management.modelviz import generate_graph_data
  
  
  class ModelVizTests(SimpleTestCase):
      @skipIf(six.PY3, 'FIXME Python 3 renders labels funny, see below')
      def test_generate_graph_data_can_render_label(self):
          app_labels = ['auth']
          data = generate_graph_data(app_labels)
  
          models = data['graphs'][0]['models']
          user_data = [x for x in models if x['name'] == 'User'][0]
          relation_labels = [x['label'] for x in user_data['relations']]
          self.assertIn("groups (user)", relation_labels)
  
      @skipUnless(six.PY3, 'DELETEME Python 3 should render the same as Python 2')
      def test_generate_graph_data_formats_labels_as_bytes(self):
          app_labels = ['auth']
          data = generate_graph_data(app_labels)
  
          models = data['graphs'][0]['models']
          user_data = [x for x in models if x['name'] == 'User'][0]
          relation_labels = [x['label'] for x in user_data['relations']]
          self.assertIn("groups (b'user')", relation_labels)
  
subject: document funny graph labels for reverse relation names in py3