sort order for strings of digits

[Chris Angelico]

On Thu, Nov 1, 2012 at 10:44 AM, Steven D'Aprano
<steve+comp.lang.python at pearwood.info> wrote:
> On the contrary. If you are using cmp with sort, your sorts are slow, and
> you should upgrade to using a key function as soon as possible.
>

But cmp_to_key doesn't actually improve anything. So I'm not sure how
Py3 has achieved anything; Py2 supported key-based sorting already.

ChrisA