Was a art director of M1 , M2 , M3 , M4 , and M5 a person
SELECT count(*) WHERE {
?x0 a ns:people.person .
?x0 ns:film.film_art_director.films_art_directed M1 .
?x0 ns:film.film_art_director.films_art_directed M2 .
?x0 ns:film.film_art_director.films_art_directed M3 .
?x0 ns:film.film_art_director.films_art_directed M4 .
?x0 ns:film.film_art_director.films_art_directed M5
}