question: Was M0 's writer a distributor of M1 and M2
query: SELECT count(*) WHERE {
  ?x0 ns:film.film_distributor.films_distributed/ns:film.film_film_distributor_relationship.film M1 .
  ?x0 ns:film.film_distributor.films_distributed/ns:film.film_film_distributor_relationship.film M2 .
  ?x0 ns:film.writer.film M0
  }