I had a Hadoop map-reduce job that kept timing out, which led to this interesting discovery:
$ time ./json-parser-test.py
$ time ./json-parser-test-no-speedups.py
$ time jython ./json-parser-test-no-speedups.py
Moral: use Java-based JSON libraries if you have to use Jython and JSON. Also, Java sucks.
I’m just going on record to state that the two reasons I’ve seen on the net for lack of tree-based collections in the Python standard library — (1) that they have bad locality (gee, very unlike huge memory-hogging randomized hash tables, oh and just try scanning one of those…), and (2) that Python makes it so simple to write your own, just do that! (well, yes I can and have, but hey it’s 2011 already, rbtrees are like 40 years old!) — are inane.