[Django]-Django's timezone.now does not show the right time

119👍

See question #2 in the "Usage" section of the Django docs.

>>> from django.utils import timezone
>>> timezone.localtime(timezone.now())

Since the doc above also talks about a best practice, including an excerpt below:

How can I obtain the local time in the current time zone?

Well, the first question is, do you really need to?

You should only use local time when you’re interacting with humans,
and the template layer provides filters and tags to convert datetimes
to the time zone of your choice.

Furthermore, Python knows how to compare aware datetimes, taking into
account UTC offsets when necessary. It’s much easier (and possibly
faster) to write all your model and view code in UTC. So, in most
circumstances, the datetime in UTC returned by
django.utils.timezone.now() will be sufficient.

4👍

from django.utils import timezone
time = timezone.localtime() 

It will give your local time that whatever your TIME_ZONE set to.

time = timezone.localtime(timezone.now()) # same result, but it is redundant.

1👍

The reason it works in the template but not in the view python code is somewhat in the docs:
https://docs.djangoproject.com/en/3.1/ref/settings/#std:setting-TIME_ZONE

"….. this is the default time zone that Django will use to display datetimes in templates and to interpret datetimes entered in forms."

This is why {{ now|date:"G" }} prints 16 (Moscow time) prints the Moscow time!

Another note is timezone.now() in a normally configured Django app will pick up whatever TIME_ZONE is set to in the settings (‘America/New_York’ in example below). But can be overridden as well (see below to Paris for example in a middleware or directly in a view for that request)

In [27]: timezone.localtime(timezone.now())

Out[27]: datetime.datetime(2021, 2, 23, 1, 53, 49, 793743, tzinfo=<DstTzInfo 'America/New_York' EST-1 day, 19:00:00 STD>)

In [29]: timezone.activate(pytz.timezone("Europe/Paris"))

In [30]: timezone.localtime(timezone.now())

Out[30]: datetime.datetime(2021, 2, 23, 7, 54, 19, 21898, tzinfo=<DstTzInfo 'Europe/Paris' CET+1:00:00 STD>)

0👍

django’s use_tz = True returns datetime object in timezone. if set to false, it uses system default (locale) time which is naïve.
I performed a small experiment to clarify this confusion

test1: when
use_tz = true; timezone= us/eastern; system timezone: UTC+5:30

datetime.datetime.today() # returned naive datetime with locale time
timezone.now() returned # UTC
timezone.localtime() # returned us/eastern 

test2: when
use_tz = true; timezone= us/eastern; system timezone: UTC-5

datetime.datetime.today() # returned naive datetime in with locale time
timezone.now() # returned UTC timezone
timezone.localtime() # in US/eastern timezone

test3: when
use_tz = False; timezone= us/eastern; system timezone: UTC-5

timezone.now() # returned naive datetime with system time
timezone.localtime() # returned traceback ValueError: localtime() cannot be applied to a naive datetime

test4: when
use_tz = False; timezone= UTC; system timezone: UTC+5:30

datetime.datetime.today() # returned naive datetime in system timezone
timezone.now() # returned naive datetime in system timezone
timezone.localtime() # returned traceback

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