I think this workaround is not necessary. I suspect your ipy is compiled by hand (not installed with msi) and such a version have a bad habit of leaving invalid __future__.py in pythonpath.
In my case, all I have to do to fix it is to remove "bad" version.

    rm /home/rejap/github/IronLanguages/bin/Debug/Lib/__future__.py

I have to do it after each compilation