Checking out the zoneinfo
module in Python 3.9, I was wondering if it also offers a convenient option to retrieve the local time zone (OS setting) on Windows.
On GNU/Linux, you can do
from datetime import datetime
from zoneinfo import ZoneInfo
naive = datetime(2020, 6, 11, 12)
aware = naive.replace(tzinfo=ZoneInfo('localtime'))
but on Windows, that throws
ZoneInfoNotFoundError: 'No time zone found with key localtime'
so would I still have to use a third-party library? e.g.
import time
import dateutil
tzloc = dateutil.tz.gettz(time.tzname[time.daylight])
aware = naive.replace(tzinfo=tzloc)
Since time.tzname[time.daylight]
returns a localized name (German in my case, e.g. 'Mitteleuropäische Sommerzeit'), this doesn't work either:
aware = naive.replace(tzinfo=ZoneInfo(tzloc))
Any thoughts?
p.s. to try this on Python < 3.9, use backports
(see also this answer):
pip install backports.zoneinfo
pip install tzdata # needed on Windows
You don't need to use zoneinfo to use the system local time zone. You can simply pass None
(or omit) the time zone when calling datetime.astimezone
.
From the docs:
If called without arguments (or with
tz=None
) the system local timezone is assumed. The.tzinfo
attribute of the converted datetime instance will be set to an instance of timezone with the zone name and offset obtained from the OS.
Thus:
from datetime import datetime
naive = datetime(2020, 6, 11, 12)
aware = naive.astimezone()