dateformat.py 文件源码

def I(self):
        "'1' if Daylight Savings Time, '0' otherwise."
        try:
            if self.timezone and self.timezone.dst(self.data):
                return '1'
            else:
                return '0'
        except Exception:
            # pytz raises AmbiguousTimeError during the autumn DST change.
            # This happens mainly when __init__ receives a naive datetime
            # and sets self.timezone = get_default_timezone().
            return ''