Get tz offset from string

Question

I have a date which is in local time:

date: "2013-12-02 22:00:00"

and another value the tz:

timezone_offset: "GMT-0800"

If I : dateutil.parser.parse(date).isoformat() I will get:

"2013-12-02T22:00:00+0000"

---

I want to implement the date in ISO format with the tz info and get a result of:

"2013-12-02T22:00:00-0800"

Something close to: parse(date,tzinfos=??).isoformat() ? How can I get the tzinfo from the string timezone_offset ?

Answer 1

>>> from dateutil.parser import parse
>>> dt = parse("2013-12-02 22:00:00" + "GMT+0800")
>>> dt.isoformat()
'2013-12-02T22:00:00-08:00'

Note: the sign is reversed.

You could also do it using only stdlib:

>>> from datetime import datetime
>>> dt = datetime.strptime("2013-12-02 22:00:00", "%Y-%m-%d %H:%M:%S")
>>> dt = dt.replace(tzinfo=FixedOffset(-8*60, "GMT+0800"))
>>> dt.isoformat()
'2013-12-02T22:00:00-08:00'

where FixedOffset is taken from datetime docs:

from datetime import tzinfo, timedelta

class FixedOffset(tzinfo):
    """Fixed offset in minutes east from UTC."""

    def __init__(self, offset, name):
        self.__offset = timedelta(minutes = offset)
        self.__name = name

    def utcoffset(self, dt):
        return self.__offset

    def tzname(self, dt):
        return self.__name

    def dst(self, dt):
        return timedelta(0)

Here's the same using pytz module:

>>> from datetime import datetime
>>> import pytz
>>> dt = datetime.strptime("2013-12-02 22:00:00", "%Y-%m-%d %H:%M:%S")
>>> dt = pytz.timezone('Etc/GMT+8').localize(dt)
>>> dt.isoformat()
'2013-12-02T22:00:00-08:00'