The `network` object would never be in a list of network names (strings), and without `greedy=True` arg as the `docker-py` API docs note, the containers will not be part of the results, thus always returning an empty list which was not intended..
Now the network will properly match the current networks for pytest container, avoiding duplicate connect attempts, and the network list result will actually have containers to count when filtering by length.
When the container runs with host networking instead of the default bridge, the `$HOSTNAME` / `/etc/hostname` reflects that of the host instead of the container ID , which causes the pytest container to get removed accidentally.
Using a container name instead we can more reliably target the container to avoid removing it, should we need to run with host networking instead.
The original `/.dockerenv` approach is no longer valid, and context wise we're only using this for the test suite, so using an ENV in that container is a better solution.
