def METHOD_NAME(self, serialized: str, filename: str) -> Tuple[List[str], List[str]]:
    """
    Upgrades preferences to have the new version number.
    :param serialized: The original contents of the preferences file.
    :param filename: The file name of the preferences file.
    :return: A list of new file names, and a list of the new contents for
    those files.
    """
    parser = configparser.ConfigParser(interpolation = None)
    parser.read_string(serialized)
    # Update version number.
    parser["general"]["version"] = "7"
    # Update visibility settings to include new top_bottom category
    if "visible_settings" in parser["general"]:
        parser["general"]["visible_settings"] += ";top_bottom"
    if "cura" in parser and "categories_expanded" in parser["cura"] and any([setting in parser["cura"]["categories_expanded"] for setting in self._moved_visibility_settings]):
        parser["cura"]["categories_expanded"] += ";top_bottom"
    # If the account scope in 4.8 is outdated, delete it so that the user is enforced to log in again and get the
    # correct permissions.
    if "ultimaker_auth_data" in parser["general"]:
        ultimaker_auth_data = json.loads(parser["general"]["ultimaker_auth_data"])
        if set(Account.CLIENT_SCOPES.split(" ")) - set(ultimaker_auth_data["scope"].split(" ")):
            parser["general"]["ultimaker_auth_data"] = "{}"
    result = io.StringIO()
    parser.write(result)
    return [filename], [result.getvalue()]