def add_args(parser):
    """
    parser : argparse.ArgumentParser
    return a parser added with args required by fit
    """
    # Training settings
    parser.add_argument(
        "--input_dir",
        type=str,
        default="/work/hideaki-t/dev/FedML/data/MNIST",
        metavar="I",
        help="input_path",
    )

    parser.add_argument(
        "--output_dir",
        type=str,
        default="/work/hideaki-t/dev/NAIST-Experiments/data/label_flip",
        metavar="O",
        help="input_path",
    )

    parser.add_argument(
        "--flip_ratio",
        type=float,
        default=0.3,
        metavar="F",
        help="flip ratio",
    )

    return parser