Were M1 , M2 , and M3 executive produced and written by a film editor
SELECT count(*) WHERE {
?x0 a ns:film.editor .
M1 ns:film.film.executive_produced_by ?x0 .
M1 ns:film.film.written_by ?x0 .
M2 ns:film.film.executive_produced_by ?x0 .
M2 ns:film.film.written_by ?x0 .
M3 ns:film.film.executive_produced_by ?x0 .
M3 ns:film.film.written_by ?x0
}