Modify option for list type? #2

First, great tool! I was looking for something exactly like this for a long time and I was happy to find this.
I would like to know: would it be possible to have a different setup for list arguments? Right now, it requires calling the argument as many times as elements in the list (e.g. --my_list 1 --my_list 2 etc) which can be cumbersome for long list or long argument names. Another option would be to use the nargs option. I tested it and it works by modifying a few lines:
At

with nargs set to 1 by default, and to '+' if annotation is iterable, here:

Let me know if you consider implementing it, otherwise, I'll fork the repository, but I would prefer to stick to this repo if I can since it can be easily installed with pip.