Who wrote M2 , edited M1 , wrote a film , and directed M3
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:people.person .
?x0 ns:film.director.film M3 .
?x0 ns:film.editor.film M1 .
?x0 ns:film.writer.film ?x1 .
?x0 ns:film.writer.film M2 .
?x1 a ns:film.film
}