def test_form_class(self):
        self.failUnless(self.backend.get_form_class(_mock_request()) is forms.RegistrationForm)
Return the index of the first child whose class does *not* match.
dataset/ETHPy150Open nathanborror/django-registration/registration/tests/backends.py/DefaultRegistrationBackendTests.test_form_class--crossover with--dataset/ETHPy150Open adieu/allbuttonspressed/docutils/nodes.py/Element.first_child_not_matching_class