Here's an alternate idea I thought of now. Maybe `path.path` should be a pointer to the same `Path` object, so every function will do this: 

    str(arg.path) if hasattr(arg, 'path') else arg

What I like about this is that it avoids having the path argument be a string. I don't like misnomers :)

I'd understand though if people won't like this suggestion since it introduces another step, of turning the path back into a string.