I agree that -V is more common. I have used a few things that use -v for version though (I think `ruby` does, which led to some confusion for me the first time

I agree that -V is more common. I have used a few things that use -v for version though (I think `ruby` does, which led to some confusion for me the first time I tried to pass that to `python` and instead of getting the version number found myself in a more chatty than normal python shell).