I'm going to be a super pedant today. :-) Quoth 257:

> ...prescribes the function or method's effect as a command ("Do this", "Return that"), not as a description; e.g. don't write "Returns the pathname ...".

And then, as per http://legacy.python.org/dev/peps/pep-0257/#multi-line-docstrings, place the closing quotes on a line by themselves. To be maximally consistent with the rest of the (good) codebase, leave a blank line before the closing quotes.