Were M1 and M2 distributed by a director of M0
SELECT count(*) WHERE {
?x0 ns:film.director.film M0 .
M1 ns:film.film.distributors/ns:film.film_film_distributor_relationship.distributor ?x0 .
M2 ns:film.film.distributors/ns:film.film_film_distributor_relationship.distributor ?x0
}