raise 404 錯誤：

def detail(request, album_id):
    try:
        album = Album.objects.filter(pk=album_id)
    except Album.DoesNotExist:
        raise Http404("Album does not exist")

    context = {
        "album":album,
    }

    return render(request, "music/detail.html", context)

里面的：

    try:
        album = Album.objects.filter(pk=album_id)
    except Album.DoesNotExist:
        raise Http404("Album does not exist")

等價于：

album = get_object_or_404(Album, pk=album_id)