dct = {'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5}
sorted(list(dct.items()), key=itemgetter(1), reverse=True)
map(itemgetter(0), sorted(list(dct.items()), key=itemgetter(1), reverse=True))
finding top k largest keys in a dictionary python