text: from django.test import TestCase
  
  from waffle import get_waffle_flag_model
  from waffle.models import Switch, Sample
  
  
  class ModelsTests(TestCase):
      def test_natural_keys(self):
          flag = get_waffle_flag_model().objects.create(name='test-flag')
          switch = Switch.objects.create(name='test-switch')
          sample = Sample.objects.create(name='test-sample', percent=0)
  
          self.assertEqual(flag.natural_key(), ('test-flag',))
          self.assertEqual(switch.natural_key(), ('test-switch',))
          self.assertEqual(sample.natural_key(), ('test-sample',))
  
          self.assertEqual(get_waffle_flag_model().objects.get_by_natural_key('test-flag'), flag)
          self.assertEqual(Switch.objects.get_by_natural_key('test-switch'), switch)
          self.assertEqual(Sample.objects.get_by_natural_key('test-sample'), sample)
  