Were M3 and M4 written by M1 's Mexican director and edited by a editor of M2
SELECT count(*) WHERE {
?x0 ns:film.director.film M1 .
?x0 ns:people.person.nationality ns:m.0b90_r .
?x1 ns:film.editor.film M2 .
M3 ns:film.film.edited_by ?x1 .
M3 ns:film.film.written_by ?x0 .
M4 ns:film.film.edited_by ?x1 .
M4 ns:film.film.written_by ?x0
}