question: Did a film editor play M1 , M2 , and M3 , play M4 , and play M5 and M6
query: SELECT count(*) WHERE {
  ?x0 a ns:film.editor .
  ?x0 ns:film.actor.film/ns:film.performance.character M1 .
  ?x0 ns:film.actor.film/ns:film.performance.character M2 .
  ?x0 ns:film.actor.film/ns:film.performance.character M3 .
  ?x0 ns:film.actor.film/ns:film.performance.character M4 .
  ?x0 ns:film.actor.film/ns:film.performance.character M5 .
  ?x0 ns:film.actor.film/ns:film.performance.character M6
  }