Converting python datetime to timestamp and back in UTC still uses local timezone -

i'm working code gives me utc timestamps , want convert them appropriate datetimes. unfortunately when test simple cases pytz datetime has added 6 hours (the cst offset utc). need keep timezone data correct because calculating difference between other timezones well. ideas why , how convert utc timestamp utc datetime?

in [1]: import pytz  in [2]: datetime import datetime  in [3]: import time  in [4]: datetime.fromtimestamp(time.mktime(datetime(7,1,1, tzinfo=pytz.utc).timetuple()), tz=pytz.utc) out[4]: datetime.datetime(2007, 1, 1, 6, 0, tzinfo=<utc>)  in [5]: datetime.fromtimestamp(time.mktime(datetime(7,1,1).utctimetuple()), tz=pytz.utc) out[5]: datetime.datetime(2007, 1, 1, 6, 0, tzinfo=<utc>)  in [6]: datetime.fromtimestamp(time.mktime(datetime(7,1,1).utctimetuple())) out[6]: datetime.datetime(2007, 1, 1, 0, 0) 

to naive datetime object represents time in utc "seconds since epoch" timestamp:

from datetime import datetime  utc_dt = datetime.utcfromtimestamp(ts) 

if want aware datetime object utc timezone:

import pytz  aware_utc_dt = utc_dt.replace(tzinfo=pytz.utc) 

to convert other timezone:

tz = pytz.timezone('america/montreal') dt = aware_utc_dt.astimezone(tz) 

to convert timestamp aware datetime object in given timezone directly:

dt = datetime.fromtimestamp(ts, tz)