Are subcommand arg groups supported?
If supported, how to config in yaml file?
found how to do that by myself.
To everyone else: the answer appears to be yes, and if you want to specify them via yaml, just indent the groups keyword to a child of your subcommand key (same level as args, about, etc).
Thanks for taking the time to actually say the answer @jpeddicord
I'm also OK with people opening issues to ask the question again, or join the Gitter chat to ask 馃槃