ipython/ipython — pull request #5042 by takluyver (2014-02-06 00:12:30+00:00)
Title: Remove duplicated Channel ABC classes.

These were moved to IPython.kernel.channelsabc, but the old copies were retained somehow.

Should we import them back into managerabc for backwards compatibility if third party code has imported them from there? It seems unlikely that they'd be used outside our codebase.