def METHOD_NAME(obj, msg):
    short_id = obj.short_id
    msg = msg+" short_id="+short_id
    already = seen.get(short_id)
    if already:
        assert already == obj.id.hex
    else:
        seen[short_id] = obj.id.hex
        lookup = testrepo[short_id]
        assert obj.id == lookup.id