mpsd-software-environment.py

                subp.add_argument(
                    "--toolchains",  # first option defines attribute
                    # name `args.toolchains` in `args = parser_args()`
                    "--toolchain",  # allow singular as alternative
                    # (-> creates attribute `args.toolchains` if used)
                    type=str,
                    dest="toolchains",
                    nargs="+",
                    default="NONE",
                    help=tool_chain_help,
                )
                subp.add_argument(
                    "--enable-build-cache",
                    action="store_true",
                    help=(
                        "Enable Spack build cache. Useful for reinstallation but "
                        "consumes time and disk space."
                    ),
                )
    # Carry out the action
    args = parser.parse_args()

    # target dir is the place where this script exists. the
    root_dir = Path(os.path.dirname(os.path.realpath(__file__)))

    set_up_logging(
        args.loglevel,
        get_installer_log_file_path(args.release, args.action, root_dir),
    )

    # Check the command and run related function
    if args.action == "remove":
        remove_environment(args.release, args.toolchains, root_dir)
    elif args.action == "start-new":
        start_new_environment(args.from_release, args.to_release, root_dir)
    elif args.action == "install":
        install_environment(
            args.release, args.toolchains, root_dir, False, args.enable_build_cache
        )
    elif args.action == "prepare":
        prepare_environment(args.release, root_dir)
    elif args.action == "available":
        get_available_toolchains(args.release)
    else:
        message = (
            f"No known action found ({args.action=}). Should probably never happen."
        )
        logging.error(message)
        raise NotImplementedError(message)


if __name__ == "__main__":
    main()