Comment 1 for bug 1990992

I think this particular exception is not caused by the Blowfish cipher deprecation output(which was probably a warning). The line that carries the fatal information is:

> /tmp/auto_lint.pid already exists, exiting

Which is coming from the code block that ensures there's only one instance of the `auto_lint.py` process executing at any given moment. Usually this script is run on a cronjob, which is installed to the system during the install hook of the juju-lint charm. I said "usually" because there are two instances where this script is run as a subprocess by the charm itself:
1 - during install: after the cronjob installation is completed, the script is run once.
2 - during config-changed.

Since we are seeing this as an exception in the charm logs, I think one of the above event handlers were running while the cronjob had already been triggered before and it was still running.