Pickling, for one. >>> nt = namedtuple('nt', 'a b') >>> nt10k = [nt(1, 2) for i in range(10000)] >>> dict10k = [{'a':1, 'b':2} for i in range(10000)] >

Pickling, for one. >>> nt = namedtuple('nt', 'a b') >>> nt10k = [nt(1, 2) for i in range(10000)] >>> dict10k = [{'a':1, 'b':2} for i in range(10000)] >>> timeit pickle.dumps(nt10k) 10 loops, best of 3: 26.3 ms per loop >>> timeit pickle.dumps(dict10k) 100 loops, best of 3: 2.49 ms per loop