docs: public Set<Pair<Unifier, SemanticDifference>> getMultiUnifierWithSemanticDiff(ReasonerAtomicQuery parent){
          return this.getMultiUnifier(parent, UnifierType.SUBSUMPTIVE).stream()
                  .map(u -> new Pair<>(u, this.getAtom().semanticDifference(parent.getAtom(), u)))
                  .collect(Collectors.toSet());
      }