'Test with an invalid action.'

def test_bad_action(self):

    action = 'robot-not-an-action'
    url = reverse('students_update_enrollment', kwargs={'course_id': self.course.id.to_deprecated_string()})
    response = self.client.post(url, {'identifiers': self.enrolled_student.email, 'action': action})
    self.assertEqual(response.status_code, 400)
