[Answer]-Python: Fastest way to make dict from list of dicts

works on python 2.6 +

use the dict constructor with enumerate.

list_of_dicts = [
    {'completed__sum': 1, 'offer__count': 2, 'offer': 1},
    {'completed__sum': 0, 'offer__count': 1, 'offer': 2}]

dictionary = dict((d['offer'], dict((k, v) for k, v in d.items() if k != 'offer')) for d in list_of_dicts)

print dictionary
>>> 
{1: {'completed__sum': 1, 'offer__count': 2}, 2: {'completed__sum': 0, 'offer__count': 1}}

edit: just found a much better way to do this. if you arent using the list anymore and are going to keep only the final results.

dictionary = dict((d.pop('offer'), d) for d in list_of_dicts)