@Override
    protected void undoCommand() {
        final Set<Geocache> caches = DataStore.loadCaches(oldLists.keySet(), LoadFlags.LOAD_CACHE_OR_DB);
        DataStore.addToLists(caches, oldLists);
    }
Removes the caches of the selected list from all other lists.
main/src/main/java/cgeo/geocaching/command/MakeListUniqueCommand.java