_LOGGER no longer working

I just did an “apt update” on my Ubuntu 18.04 server running HA in a pyvenv. I’m in the process of developing a custom platform, but the _LOGGER function no longer works (nothing appears in hass.log). Is anyone else seeing this?

These were my most recently updated packages:
The following packages will be upgraded:
libpython3.6 libpython3.6-dev libpython3.6-minimal libpython3.6-stdlib python3.6 python3.6-dev python3.6-minimal python3.6-venv