https://bugzilla.wikimedia.org/show_bug.cgi?id=66950
--- Comment #1 from John Mark Vandenberg jayvdb@gmail.com --- The 'ov' bug was caused by Change-Id: Ibdfc17e86814a905e212bd454deba36c7995df4f
The 'base_dir' appears to have been in the system for quite a long time. I havent bisected it, but it looks to go back to before the 2008 rename from config.py to config2.py.