val=datetime.datetime.strptime("2015-02-01",'%Y-%m-%d').date()
zon=pytz.timezone('US/Pacific')
dt=datetime.datetime(val.year,val.month,val.day, tzinfo=zon)
print dt,zon


output:
2015-02-01 00:00:00-07:53 US/Pacific

output should be
2015-02-01 00:00:00-08:00 US/Pacific

Datetimes in local timezones should be created using localize():

>>> zon.localize(datetime.datetime(2015, 2, 1)).isoformat()
'2015-02-01T00:00:00-08:00'

See the two supported methods of creating local datetimes at: http://pytz.sourceforge.net

i dont need local timezone
i need other timezones like: (US/Pacific)

zon=pytz.timezone('America/New_York')
dt=datetime.datetime(2014,02,01, tzinfo=zon)
print dt,zon

=> 2015-02-01 00:00:00-04:56 America/New_York

zon=pytz.timezone('Asia/Kolkata')
dt=datetime.datetime(2014,02,01, tzinfo=zon)
print dt,zon

=>2015-02-01 00:00:00+05:53 Asia/Kolkata

all most for all timezones it is giving erroronous outputs
we are dealing many timezones

pytz is not a part of the python standard library, it is a 3rd party product.  Please reread Simeon's message (he's talking about any timezone), and if you have further questions ask on whatever support forum pytz has, or on the python-list mailing list.

santhosh,

I would be interested to know how this gets resolved.  I find it strange that zon gets fractional UTC offset:

>>> zon
<DstTzInfo 'US/Pacific' LMT-1 day, 16:07:00 STD>

If you ask on a pytz-related forum, please post a link here.

Some other cases:

>>> pytz.timezone('US/Eastern')
<DstTzInfo 'US/Eastern' LMT-1 day, 19:04:00 STD>

>>> pytz.timezone('US/Central')
<DstTzInfo 'US/Central' LMT-1 day, 18:09:00 STD>

>>> pytz.timezone('Asia/Kolkata')
<DstTzInfo 'Asia/Kolkata' LMT+5:53:00 STD>

but

>>> pytz.timezone('Europe/Paris')
<DstTzInfo 'Europe/Paris' LMT+0:09:00 STD>

It looks like pytz documentation [1] specifically warns about this kind of usage:

"""
Unfortunately using the tzinfo argument of the standard datetime constructors ‘’does not work’’ with pytz for many timezones.
"""


[1] http://pytz.sourceforge.net/#localized-times-and-date-arithmetic

Thanks simeon.visser,
I understood your point. Didn't got your point earlier.

Hey belopolsky,
Here is the solution
val=datetime.datetime.strptime("2015-02-01",'%Y-%m-%d').date()
zon=pytz.timezone('US/Pacific')

Bad Code:
dt=datetime.datetime(val.year,val.month,val.day, tzinfo=zon)
Good Code:
dt=zon.localize(datetime.datetime(val.year,val.month,val.day))

In Linux, good code works perfectly

Both code are working perfectly in Mac