def activity_info_oldurl(request, course_slug, activity_slug, tail):
    """
    Redirect old activity URLs to new (somewhat intelligently: don't redirect if there's no activity there)
    """
    course = get_object_or_404(CourseOffering, slug=course_slug)
    activity = get_object_or_404(Activity, slug=activity_slug, offering=course)
    act_url = reverse('offering:activity_info', kwargs={'course_slug': course.slug, 'activity_slug': activity.slug})
    return HttpResponseRedirect(act_url + tail)