def METHOD_NAME(self, serialized: str, filename: str) -> Tuple[List[str], List[str]]:
    """
    Upgrades instance containers to remove the settings that were removed in this version.
    It also changes the instance containers to have the new version number.
    This removes any settings that were removed in the new Cura version and updates settings that need to be updated
    with a new value.
    :param serialized: The original contents of the instance container.
    :param filename: The original file name of the instance container.
    :return: A list of new file names, and a list of the new contents for
    those files.
    """
    parser = configparser.ConfigParser(interpolation = None, comment_prefixes = ())
    parser.read_string(serialized)
    # Update version number.
    parser["metadata"]["setting_version"] = "20"
    if "values" in parser:
        # Remove deleted settings from the instance containers.
        for removed in _removed_settings:
            if removed in parser["values"]:
                del parser["values"][removed]
        # Replace Outer Before Inner Walls with equivalent setting.
        if "outer_inset_first" in parser["values"]:
            old_value = parser["values"]["outer_inset_first"]
            if old_value.startswith("="):  # Was already a formula.
                old_value = old_value[1:]
            parser["values"]["inset_direction"] = f"='outside_in' if ({old_value}) else 'inside_out'"  # Makes it work both with plain setting values and formulas.
        # Replace Equalize Filament Flow with equivalent setting.
        if "speed_equalize_flow_enabled" in parser["values"]:
            old_value = parser["values"]["speed_equalize_flow_enabled"]
            if old_value.startswith("="):  # Was already a formula.
                old_value = old_value[1:]
            parser["values"]["speed_equalize_flow_width_factor"] = f"=100 if ({old_value}) else 0"  # If it used to be enabled, set it to 100%. Otherwise 0%.
    result = io.StringIO()
    parser.write(result)
    return [filename], [result.getvalue()]