Different datetime.strftime output with same locale settings

Question

I use python 2.7 and it turned out that datetime.strftime produces different output on different environments (both unix-based) with the same locale settings.

locale.setlocale(locale.LC_ALL, ('RU', 'utf-8'))
print locale.getlocale()
print datetime.date.today().strftime("%Y %d %B, %A")

On first env I got:

('ru_RU', 'UTF-8')

2016 21 января, четверг (month name is in genitive form)

On the second:

('ru_RU', 'UTF-8')

2016 21 Январь, Четверг (month name is in infinitive form)

As you can see there are also some differences in upper/lowercase letters. PYTHONIOENCODING is set to utf_8 in both cases.

What is the reason of this behavior and more important is there a way to make the second env work the way the first does?

first - 2.7.10, second - 2.7.6. It seems like we have an answer, right? I synch them and than write back. — superduper, Jan 21 '16 at 14:50
does [using `babel`](http://stackoverflow.com/a/34603979/4279) produce the same results on your different systems? — jfs, Jan 21 '16 at 16:42
@wayne It appeared to be harder than I thought: virtenv based on 2.7.10 now produce difficulties with other external libs( so taking [this answer](http://stackoverflow.com/a/34927103/5213700) into consideration I just gonna give up and just code it manually — superduper, Jan 21 '16 at 20:04

Martijn Pieters · Accepted Answer · 2016-01-21T20:56:39.433

You are looking at the output of the C strftime() call here; Python delegates to it. That function picks those strings from locale files stored outside the control of Python.

See the locale man page for a description of the file format; you are looking for the LC_TIME mon and day lists here.

On Mac OS X stores things slightly differently, the files are stored in /usr/share/locale/; for ru_RU time definitions there is a file called /usr/share/locale/ru_RU.UTF-8/LC_TIME; it puts values one per line in a certain order. The first 24 lines are months (abbreviated and full), for example; with the full month names defined as:

января
февраля
марта
апреля
мая
июня
июля
августа
сентября
октября
ноября
декабря

Because this is OS and system specific, you'd have to use a different system altogether to format your dates if you need these strings to be consistent across different platforms.

If you are trying to parse a date string, you won't get far with the datetime or time modules. Try the dateparser project instead, which understands the different Russian forms:

>>> import dateparser
>>> dateparser.parse(u'2016 21 января, четверг')
datetime.datetime(2016, 1, 21, 0, 0)
>>> dateparser.parse(u'2016 21 Январь, Четверг')
datetime.datetime(2016, 1, 21, 0, 0)

Unfortunately my aim is not to format but to parse some strings into dates. So if I get you right my only option is to code it manually or find external lib( — superduper, Jan 21 '16 at 20:08
@superduper: I'm afraid so. Parsing dates using *local natural language* is a hard problem though. — Martijn Pieters, Jan 21 '16 at 20:35
@superduper: I've added a alternative that works with Russian dates, at least. — Martijn Pieters, Jan 21 '16 at 20:56

score 0 · Answer 2 · answered Jan 21 '16 at 15:00

0

Python's datetime.strftime wraps time.strftime, and the latter delegates to the underlying C's strftime(3). Apparently, that's what it returns.

answered Jan 21 '16 at 15:00

ivan_pozdeev

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Different datetime.strftime output with same locale settings

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