def test_order_form_mixin(self):
        def get_order_by_choices():
            return (('last_name', 'Last Name'),
                    ('first_name', 'First Name'))

        class Form(gf.OrderFormMixin, forms.Form):
            def get_order_by_choices(self):
                return get_order_by_choices()

        form = Form()

        self.assertTrue(form.fields in 'order_by')
        self.assertTrue('order_reverse' in form.fields)

        self.assertEqual(form.fields['order_by'].choices,
                         list(get_order_by_choices()))
dataset/ETHPy150Open peopledoc/django-generic-filters/django_genericfilters/tests/forms.py/FormTestCase.test_order_form_mixin/swapped operands of `in`