https://bugzilla.wikimedia.org/show_bug.cgi?id=71454
--- Comment #1 from John Mark Vandenberg jayvdb@gmail.com --- The cause of the problem appears to be flickrapi 1.4.4 which calls logging.basicConfig(), which is not appropriate for a library.
https://bitbucket.org/sybren/flickrapi/src/e91ab5c64c7ed036a7397474ec31f9b16...
The bug stopped happening on travis because script_tests first checks for ImageTk, which fails for travis builds, so flickrapi isnt loaded
https://travis-ci.org/wikimedia/pywikibot-core/jobs/37419168
"flickrripper depends on ImageTk, which isnt available: No module named ImageTk"