question: Were M2 and M4 written by a screenwriter , executive produced by a person , and written by M3
query: SELECT count(*) WHERE {
  ?x0 a ns:people.person .
  ?x1 a ns:film.writer .
  M2 ns:film.film.executive_produced_by ?x0 .
  M2 ns:film.film.written_by ?x1 .
  M2 ns:film.film.written_by M3 .
  M4 ns:film.film.executive_produced_by ?x0 .
  M4 ns:film.film.written_by ?x1 .
  M4 ns:film.film.written_by M3
  }