components = [{"name": "fictional-parser", "version": "1.4", "used_by": "attachment-worker"}, {"name": "fictional-mailer", "version": "2.1", "used_by": "reminders"}]
assert len({item["name"] for item in components}) == len(components)
affected = [item["used_by"] for item in components if item["name"] == "fictional-parser"]
assert affected == ["attachment-worker"]
print("review target: attachment-worker")