Commandlines is a Python library for command line application development that
supports command line argument parsing, command string validation testing, &
application logic. It has no external dependencies and provides broad Python
interpreter support.

The library supports application development with POSIX guideline compliant[*]
command argument styles, the GNU argument style extensions to the POSIX
guidelines (including long option syntax and variable position of options among
arguments), and command suite style application arguments that include one or
more sub-commands to the executable.

[*] with the exception of the short single option-argument definition syntax
that does not include an intervening space character (e.g. -ofile)

WWW: https://github.com/chrissimpkins/commandlines