question: Was a Canadian film editor that M2 was executive produced by and M4 starred a screenwriter
query: SELECT count(*) WHERE {
  ?x0 a ns:film.editor .
  ?x0 a ns:film.writer .
  ?x0 ns:film.actor.film/ns:film.performance.film M4 .
  ?x0 ns:film.producer.films_executive_produced M2 .
  ?x0 ns:people.person.nationality ns:m.0d060g
  }