Were M1 and M2 executive produced and directed by a art director
SELECT count(*) WHERE {
?x0 a ns:film.film_art_director .
M1 ns:film.film.directed_by ?x0 .
M1 ns:film.film.executive_produced_by ?x0 .
M2 ns:film.film.directed_by ?x0 .
M2 ns:film.film.executive_produced_by ?x0
}