'If we execute the exact same statement twice, the second time,
it won\'t create a Person.'

def test_get_or_create_redundant_instance(self):

    Person.objects.get_or_create(first_name='George', last_name='Harrison', defaults={'birthday': date(1943, 2, 25)})
    created = Person.objects.get_or_create(first_name='George', last_name='Harrison', defaults={'birthday': date(1943, 2, 25)})[1]
    self.assertFalse(created)
    self.assertEqual(Person.objects.count(), 2)
