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I need to convert UTC time, (on ec2 instance) to PST. I am trying to do this. 

from datetime import datetime
from pytz import timezone
import pytz

date_format='%m/%d/%Y %H:%M:%S %Z'
date = datetime.now()
print 'Current date & time is:', date.strftime(date_format)

my_timezone=timezone('US/Pacific')

date = my_timezone.localize(date)
date = date.astimezone(my_timezone)

print 'Local date & time is  :', date.strftime(date_format)

But the output is:

Current date & time is: 01/10/2012 20:01:14
Local date & time is  : 01/10/2012 20:01:14 PST

Any reason why I am not getting the right PST time?

FObersteiner
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Nish
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  • a year 2021 Python 3 answer would be e.g. [Display the time in a different time zone](https://stackoverflow.com/a/63628816/10197418) – FObersteiner Nov 23 '21 at 06:41

5 Answers5

51
from datetime import datetime
from pytz import timezone
import pytz

date_format='%m/%d/%Y %H:%M:%S %Z'
date = datetime.now(tz=pytz.utc)
print 'Current date & time is:', date.strftime(date_format)

date = date.astimezone(timezone('US/Pacific'))

print 'Local date & time is  :', date.strftime(date_format)

seems to work for me :) - timezones are confusing, slowly making a plan of what I actually want to do helps me most of the time

sleeplessnerd
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    Thanks buddy, timeszones are pain in the back, daylight savings is even more a headache! – Nish Jan 10 '12 at 20:30
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    Thanks for this. Hard to find a simple example. I got this working on google app engine with this: gaepytz. Above code works the same, only import text changes. – angelfilm entertainment Mar 08 '12 at 18:29
  • I voted down this question and answer because I I am pretty sure it is incorrect for anyone who really wants "PST". Pacific-New produces local Pacific time, not standard time. There is no difference for the January date cited, but it would be an issue in the summer. – Eli S Jul 12 '17 at 14:39
7

Do this in one line:

>>> import pytz
>>> pytz.utc.localize(datetime.utcnow()).astimezone(pytz.timezone('US/Pacific'))
datetime.datetime(2016, 5, 16, 10, 58, 18, 413399, tzinfo=<DstTzInfo 'US/Pacific' PDT-1 day, 17:00:00 DST>)
Wayne Ye
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7

By calling to localize you tell in what TZ your time is. So, in your example you say that your date is in PST, then you call astimezone for PST and get the same time which is expected. You probably need the following:

utc_dt = pytz.utc.localize(datetime.utcnow())
pst_tz = timezone('US/Pacific')
pst_dt = pst_tz.normalize(utc_dt.astimezone(pst_tz))
pst_dt.strftime(fmt)

Sorry, cannot check if this code executes - don't have this library on workstation.

real4x
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4

I think you want datetime.utcnow() if you are attempting to simulate UTC time in your example.

The other issue is that by default the object has no timezone. This does not mean that it is UTC, and I think pytz is just defaulting to localtime for that object. You need to create a new datetime object with the timezone set as UTC before you try to convert it to PST.

You can do this via

date = datetime.utcnow()
date.replace(tzinfo=pytz.utc)
Michael Merickel
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-1

if you want to calculate the current uptime based on launchtime of an EC2 instance, one can try this:

import datetime
lt_datetime = datetime.datetime.strptime(inst.launch_time, '%Y-%m-%dT%H:%M:%S')
lt_delta = datetime.datetime.utcnow() - lt_datetime
str(lt_delta)
admirableadmin
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