(self, dt)
datetime -> timedelta, positive for east of UTC, negative for west of UTC
datetime -> timedelta, positive for east of UTC, negative for west of UTC
datetime - > timedelta positive for east of UTC negative for west of UTC
def utcoffset(self, dt):
        "datetime -> timedelta, positive for east of UTC, negative for west of UTC"
        raise NotImplementedError("tzinfo subclass must override utcoffset()")
def utcoffset ( self , dt ) : raise NotImplementedError ( "tzinfo subclass must override utcoffset()" )