I attached a more complete patch to the issue #13882: it adds an optional timestamp format to os.stat(), os.lstat(), os.fstat(), os.fstatat().

Examples:

$ ./python 
Python 3.3.0a0 (default:2914ce82bf89+, Jan 30 2012, 23:07:24) 
>>> import os
>>> s=os.stat("setup.py", timestamp="datetime")
>>> s.st_mtime - s.st_ctime
datetime.timedelta(0)
>>> print(s.st_atime - s.st_ctime)
52 days, 1:44:06.191293
>>> os.stat("setup.py", timestamp="timespec").st_ctime
(1323458640, 702327236)
>>> os.stat("setup.py", timestamp="decimal").st_ctime
Decimal('1323458640.702327236')