def METHOD_NAME(self):
    option_fields = PostWithUniqField._meta.get_fields()
    uniq_mixin_fields = [i[0] for i in UniqueFieldMixin._get_fields(PostWithUniqField)]
    self.assertEqual(len(option_fields), 9)
    self.assertEqual(len(uniq_mixin_fields), 7)
    fields_to_be_excluded_from_uniq_mixin_fields = [
        f for f in option_fields
        if f.is_relation and not f.one_to_one and not (f.many_to_one and f.related_model)
    ]
    for field in fields_to_be_excluded_from_uniq_mixin_fields:
        self.assertNotIn(field, uniq_mixin_fields)