Looks good, other than the one typo I found. http://bugs.python.org/review/26304/diff/16519/Misc/HISTORY File Misc/HISTORY (right): http://bugs.python.org/review/26304/diff/16519/Misc/HISTORY#newcode2237 Misc/HISTORY:2237: attribute which allows seting custom per-pickler reduction functions. Should be "setting". http://bugs.python.org/review/26304/