question: Was a film 's sequel written by and executive produced by M0 and M1
query: SELECT count(*) WHERE {
  ?x0 ns:film.film.executive_produced_by M0 .
  ?x0 ns:film.film.executive_produced_by M1 .
  ?x0 ns:film.film.prequel ?x1 .
  ?x0 ns:film.film.written_by M0 .
  ?x0 ns:film.film.written_by M1 .
  ?x1 a ns:film.film
  }