- Cement (http://builtoncement.com)
- Cliff (http://cliff.readthedocs.org/en/latest/)
- Plumbum (http://plumbum.readthedocs.org)
- Argh (https://pypi.python.org/pypi/argh/0.24.1)
- Aaargh (https://github.com/wbolster/aaargh)
- Baker (https://pypi.python.org/pypi/Baker/)
So many more to choose from. Now we get to evaluate Click. Seems like the reason Armin wrote Click was to load options dynamically, but that's what Cliff does via stevedore (https://github.com/dreamhost/stevedore).
My favorite feature about Cliff though is: http://cliff.readthedocs.org/en/latest/complete.html which comes out of the box, but then again, there's Argcomplete (https://github.com/kislyuk/argcomplete).
EDIT: Updating from previous posters
- Naked (http://naked-py.com)
- Docopt (http://docopt.org)
- Clint (https://github.com/kennethreitz/clint)
- Argvard (https://github.com/DasIch/argvard)
- Commandr (https://github.com/tellapart/commandr)
- Argtools (https://pypi.python.org/pypi/argtools/0.1.2)
- Plac (https://pypi.python.org/pypi/plac)