Which film producer distributed M1 , M2 , M3 , M4 , M5 , and M6
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:film.producer .
?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.film_distributor.films_distributed/ns:film.film_film_distributor_relationship.film M3 .
?x0 ns:film.film_distributor.films_distributed/ns:film.film_film_distributor_relationship.film M4 .
?x0 ns:film.film_distributor.films_distributed/ns:film.film_film_distributor_relationship.film M5 .
?x0 ns:film.film_distributor.films_distributed/ns:film.film_film_distributor_relationship.film M6
}