question: Was a film producer founded by a actor of M1 , M2 , and M3
query: SELECT count(*) WHERE {
  ?x0 a ns:film.producer .
  ?x0 ns:organization.organization.founders ?x1 .
  ?x1 ns:film.actor.film/ns:film.performance.character M1 .
  ?x1 ns:film.actor.film/ns:film.performance.character M2 .
  ?x1 ns:film.actor.film/ns:film.performance.character M3
  }