erikrose/more-itertools — pull request #26 by Rosuav (2013-06-11 07:47:20+00:00)
Title: New itertool: ipartition

Not sure if this would be of interest to you, but it's something I knocked together in response to a python-list question and Tim Chase said it might be of use. It looks like you're using the MIT license? I'm okay with that, if it is.