Were M1 and M6 edited by M2 and M3 , edited by M4 and M5 , and written by a film producer
SELECT count(*) WHERE {
?x0 a ns:film.producer .
M1 ns:film.film.edited_by M2 .
M1 ns:film.film.edited_by M3 .
M1 ns:film.film.edited_by M4 .
M1 ns:film.film.edited_by M5 .
M1 ns:film.film.written_by ?x0 .
M6 ns:film.film.edited_by M2 .
M6 ns:film.film.edited_by M3 .
M6 ns:film.film.edited_by M4 .
M6 ns:film.film.edited_by M5 .
M6 ns:film.film.written_by ?x0
}