question: Was a film written by a art director , edited by M2 , and written by M1
query: SELECT count(*) WHERE {
  ?x0 a ns:film.film .
  ?x0 ns:film.film.edited_by M2 .
  ?x0 ns:film.film.written_by ?x1 .
  ?x0 ns:film.film.written_by M1 .
  ?x1 a ns:film.film_art_director
  }