Was a editor of M1 , M2 , M3 , M4 , M5 , and M6 a art director
SELECT count(*) WHERE {
?x0 a ns:film.film_art_director .
?x0 ns:film.editor.film M1 .
?x0 ns:film.editor.film M2 .
?x0 ns:film.editor.film M3 .
?x0 ns:film.editor.film M4 .
?x0 ns:film.editor.film M5 .
?x0 ns:film.editor.film M6
}