question: Was a person a film editor that M2 and M3 were directed by , were written by , and starred
query: SELECT count(*) WHERE {
  ?x0 a ns:film.editor .
  ?x0 a ns:people.person .
  ?x0 ns:film.actor.film/ns:film.performance.film M2 .
  ?x0 ns:film.actor.film/ns:film.performance.film M3 .
  ?x0 ns:film.director.film M2 .
  ?x0 ns:film.director.film M3 .
  ?x0 ns:film.writer.film M2 .
  ?x0 ns:film.writer.film M3
  }