Linter errors

[faif]

From the output of lint_python:

Run black --check .
would reformat tests/behavioral/test_strategy.py
would reformat tests/behavioral/test_publish_subscribe.py
would reformat tests/structural/test_proxy.py
Oh no! 💥 💔 💥
3 files would be reformatted, 59 files would be left unchanged.
Error: Process completed with exit code 1.