def parse_options_header(value):
    def _tokenize(string):
        for match in _option_header_piece_re.finditer(string):
            key, value = match.groups()
            key = unquote_header_value(key)
            if value is not None:
                value = unquote_header_value(value, key == 'filename')
            yield key, value

    if not value:
        return '', {}

    parts = _tokenize(';' + value)
    name = next(parts)[0]
    extra = dict(parts)
    return name, extra
Internal helper to retrieve the value for this Property from an entity.
dataset/ETHPy150Open Eforcers/gae-flask-todo/lib/werkzeug/http.py/parse_options_header--crossover with--dataset/ETHPy150Open GoogleCloudPlatform/datastore-ndb-python/ndb/model.py/Property._retrieve_value