question: What film that M5 and M6 directed was distributed by M1 and M2 and was distributed by M3 and M4
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.film .
  ?x0 ns:film.film.directed_by M5 .
  ?x0 ns:film.film.directed_by M6 .
  ?x0 ns:film.film.distributors/ns:film.film_film_distributor_relationship.distributor M1 .
  ?x0 ns:film.film.distributors/ns:film.film_film_distributor_relationship.distributor M2 .
  ?x0 ns:film.film.distributors/ns:film.film_film_distributor_relationship.distributor M3 .
  ?x0 ns:film.film.distributors/ns:film.film_film_distributor_relationship.distributor M4
  }