Hi! This seems to be pretty simple and straight-forward. You've put Python and/or Shell Script as required techniques, do you actually need these or is it just some suggestions/preferrences? I'm wondering, do you have access to a diff tool and have tried it (which might not be that helpful, if the IDs are mixed)? Have you access to, and tried, something like sort | uniq, grep, along these lines?
Do you need to perform this once or need a tool/code to do it independently/repeatedly?