Right.  Which is why you get an error if you try to use an empty directory as if it was a maildir :)

create=True creates the *directory* and initializes it.  That seems clear to me, and exactly what I would expect.  "The mailbox" is the directory.  If it already exists, it should be a Maildir folder.  I wouldn't want a program messing with an existing directory if it was invalid...it might trash my data :)

I don't think even a doc change is needed here, but if you want to propose something we can evaluate it.