pbbt and import python files

Question

I want to use pbbt (Pluggable Black-Box Testing toolkit) for testing. Let's suppose I have that structure:

├──black_box_tests
│   ├──black_box_settings.py
│   ├──input.yaml

and I want to import black_box_settings in yaml:

py: |
  import black_box_settings

I get an error ModuleNotFoundError: No module named 'black_box_settings' when try run pbbt input.yaml output.yaml --train command. There is no example of importing your own modules on the documentation page.