Which character that M1 was executive produced by and was written by wrote a film
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:fictional_universe.fictional_character .
?x0 ns:film.producer.films_executive_produced M1 .
?x0 ns:film.writer.film ?x1 .
?x0 ns:film.writer.film M1 .
?x1 a ns:film.film
}