Theres some issue with the venv upload download, which is causing an issue in the case of ppc hosts. In this case, it seems something overwrites the venv upload with a different venv that links to a different system library. The issue was only ever reproduced from a downloaded venv which suggested it was modified prior to the task starting.

A workaround to fix the hot BF in the mean time is to always install a fresh venv and don't use the uploaded venv. This is okay on ppc because the extra time to reinstall is relatively insignificant compared to the average task times on ppc.

A follow on ticket should investigate our usages of upload download and implement more security and reliability around it.