tzinfo.py 文件源码

def normalize(self, dt, is_dst=False):
        '''Correct the timezone information on the given datetime.

        This is normally a no-op, as StaticTzInfo timezones never have
        ambiguous cases to correct:

        >>> from pytz import timezone
        >>> gmt = timezone('GMT')
        >>> isinstance(gmt, StaticTzInfo)
        True
        >>> dt = datetime(2011, 5, 8, 1, 2, 3, tzinfo=gmt)
        >>> gmt.normalize(dt) is dt
        True

        The supported method of converting between timezones is to use
        datetime.astimezone(). Currently normalize() also works:

        >>> la = timezone('America/Los_Angeles')
        >>> dt = la.localize(datetime(2011, 5, 7, 1, 2, 3))
        >>> fmt = '%Y-%m-%d %H:%M:%S %Z (%z)'
        >>> gmt.normalize(dt).strftime(fmt)
        '2011-05-07 08:02:03 GMT (+0000)'
        '''
        if dt.tzinfo is self:
            return dt
        if dt.tzinfo is None:
            raise ValueError('Naive time - no tzinfo set')
        return dt.astimezone(self)