[bug] Error handling is broken on dev branch

[drobnyjt]

Description
Something upstream has caused PyO3 to stop cooperating with the error handling offered by anyhow. Anyhow's Ok() can no longer be used as a PyErr type; all that needs to be done to fix this is clarify what is to be imported from anyhow - I don't actually need anyhow's Ok(), so removing use anyhow::* seems like it fixes the issue.