Clustering the keys of a dict according to its values

[alex23]

On Nov 14, 11:24 pm, bearophileH... at lycos.com wrote:
> Alternative version:
>
> def cluster(data):
>     d = defaultdict(list)
>     pairs = enumerate(data) if isinstance(data, list) else
> data.iteritems()
>     for k, v in pairs:
>         d[v].append(k)
>     return d
>
> Bye,
> bearophile

Very nice, +1.