Not a new issue, many Python users have already written about this error. In line 128 of IOBinding.py file, please change 'str = str.split("\n", 2)[:2]" to "lst = str.split("\n", 2)[:2]". This error prevents IDLE from working correctly when a .py file is loaded. I use IDLE on Ubuntu 13.10. At every new update, I need to manually modify IOBinding.py file in /usr/lib/python2.7/idlelib directory. Please fix it. Thanks
More specifically, the bug that causes the problem was first released in the 2.7.6 release candidate 1 (pre-release, 2013-10-26) and fixed in the official 2.7.6 final release (2013-11-10). So it is somewhat surprising that you would continually re-encounter it.
Is idle-python2.7_2.7.5-8ubuntu3.1_all.deb the latest package? I downloaded it from saucy and saucy-updates repository via packages.ubuntu.com. In both cases the error is still there. I don't want to be annoying but I would like you to decompress the package and verify yourself. Tell me please If I'm wrong. Not a great problem, indeed.