Was a person a film director that M2 , M3 , and M4 were executive produced by
SELECT count(*) WHERE {
?x0 a ns:film.director .
?x0 a ns:people.person .
?x0 ns:film.producer.films_executive_produced M2 .
?x0 ns:film.producer.films_executive_produced M3 .
?x0 ns:film.producer.films_executive_produced M4
}