Message8912

It's easily tested.
>>> from datetime import datetime
>>> fmt = '%Y-%m-%d %H:%M:%S.%f'
>>> t = datetime.now(); s = datetime.strptime(t.strftime(fmt), fmt); t-s
datetime.timedelta(0, 0, 476999)
>>> t.strftime(fmt)
'2014-08-11 21:20:33.476999'

With CPython I get:
>>> t = datetime.now(); s = datetime.strptime(t.strftime(fmt), fmt); t-s
datetime.timedelta(0)

Although it surprises me in that case that test_strptime passes (without skips).