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```console
$ 03_01_flag_bool_derive --help
A simple to use, efficient, and full-featured Command Line Argument Parser
Usage: 03_01_flag_bool_derive[EXE] [OPTIONS]
Options:
-v, --verbose
-h, --help Print help
-V, --version Print version
$ 03_01_flag_bool_derive
verbose: false
$ 03_01_flag_bool_derive --verbose
verbose: true
$ 03_01_flag_bool_derive --verbose --verbose
? failed
error: the argument '--verbose' cannot be used multiple times
Usage: 03_01_flag_bool_derive[EXE] [OPTIONS]
For more information, try '--help'.
```