Conceptually the problem with this is that if you use the object to delete the folder, you now have an object with no folder...that is,
an invalid object.  Do we have any other stdlib examples of objects with a 'delete()' method...looks like bdb has a deleteMe on breakpoint objects, but it isn't clear that it tries to deal with what happens if a breakpoint object that has been deleted is accessed again.  There are also some in idlelib/tk, which I haven't looked at.

So, I guess the issue is to work out what the semantics of the object would be if delete has been called, and make sure it actually makes sense to have a delete method.