/usr/bin/python3.5:11:visit_decref:dict_traverse:subtract_refs:collect:collect_with_callback

[errors.ubuntu.com bug bridge]

The Ubuntu Error Tracker has been receiving reports about a problem regarding python3.5. This problem was most recently seen with package version 3.5.3-1ubuntu0~17.04.2, the problem page at https://errors.ubuntu.com/problem/3e76e2d1d01e0e57d852ca6e0107906c9a1faf0a contains more details, including versions of packages affected, stacktrace or traceback, and individual crash reports.
If you do not have access to the Ubuntu Error Tracker and are a software developer, you can request it at http://forms.canonical.com/reports/.