BoredHedgehog47 could it be "python" python points to python 2.7 inside your container, as opposed to python3 on your machine
(this error is python2 trying to run python 3 code)
https://stackoverflow.com/questions/20555517/using-multiple-versions-of-python
"Training classifier with command:\n python -m sfi.imagery.models.bbox_predictorv2.train