$ 03_01_flag_count_derive --help
A simple to use, efficient, and full-featured Command Line Argument Parser
Usage: 03_01_flag_count_derive[EXE] [OPTIONS]
Options:
-v, --verbose...
-h, --help Print help
-V, --version Print version
$ 03_01_flag_count_derive
verbose: 0
$ 03_01_flag_count_derive --verbose
verbose: 1
$ 03_01_flag_count_derive --verbose --verbose
verbose: 2