private static ListMap<String, Integer> allPossibilities(Set<String> dimensions) {
        ListMap<String, Integer> all = new ListMap<>();
        for (String dimension : dimensions) {
            // 20 (different dimension names) should be enough for most problems.
            for (int i = 0; i < Math.min(dimensions.size(), 20); ++i)
                all.put(dimension, i);
        }
        return all;
    }
Returns a list containing a list of all assignment possibilities for each of the given dimensions
model-integration/src/main/java/ai/vespa/rankingexpression/importer/NamingConstraintSolver.java