```console $ 04_04_custom_derive --help A simple to use, efficient, and full-featured Command Line Argument Parser Usage: 04_04_custom_derive[EXE] [OPTIONS] [INPUT_FILE] Arguments: [INPUT_FILE] some regular input Options: --set-ver set version manually --major auto inc major --minor auto inc minor --patch auto inc patch --spec-in some special input argument -c -h, --help Print help -V, --version Print version $ 04_04_custom_derive ? failed error: Can only modify one version field Usage: clap [OPTIONS] [INPUT_FILE] For more information, try '--help'. $ 04_04_custom_derive --major Version: 2.2.3 $ 04_04_custom_derive --major --minor ? failed error: Can only modify one version field Usage: clap [OPTIONS] [INPUT_FILE] For more information, try '--help'. $ 04_04_custom_derive --major -c config.toml ? failed Version: 2.2.3 error: INPUT_FILE or --spec-in is required when using --config Usage: clap [OPTIONS] [INPUT_FILE] For more information, try '--help'. $ 04_04_custom_derive --major -c config.toml --spec-in input.txt Version: 2.2.3 Doing work using input input.txt and config config.toml ```