Were M3 , M5 , and M6 written by a American Canadian screenwriter and written by M4
SELECT count(*) WHERE {
?x0 a ns:film.writer .
?x0 ns:people.person.nationality ns:m.09c7w0 .
?x0 ns:people.person.nationality ns:m.0d060g .
M3 ns:film.film.written_by ?x0 .
M3 ns:film.film.written_by M4 .
M5 ns:film.film.written_by ?x0 .
M5 ns:film.film.written_by M4 .
M6 ns:film.film.written_by ?x0 .
M6 ns:film.film.written_by M4
}