question: Was a film producer that directed M1 , M2 , and M3 a film 's star and editor
query: SELECT count(*) WHERE {
  ?x0 a ns:film.producer .
  ?x0 ns:film.actor.film/ns:film.performance.film ?x1 .
  ?x0 ns:film.director.film M1 .
  ?x0 ns:film.director.film M2 .
  ?x0 ns:film.director.film M3 .
  ?x0 ns:film.editor.film ?x1 .
  ?x1 a ns:film.film
  }