def parse(cls, value, kwds): if not value: kwds['defects'].append(errors.HeaderMissingRequiredValue()) kwds['datetime'] = None kwds['decoded'] = '' kwds['parse_tree'] = parser.TokenList() return if isinstance(value, str): value = utils.parsedate_to_datetime(value) kwds['datetime'] = value kwds['decoded'] = utils.format_datetime(kwds['datetime']) kwds['parse_tree'] = cls.value_parser(kwds['decoded'])