Which character was a executive producer and writer of M1 and M2
SELECT DISTINCT ?x0 WHERE {
?x0 a ns:fictional_universe.fictional_character .
?x0 ns:film.producer.films_executive_produced M1 .
?x0 ns:film.producer.films_executive_produced M2 .
?x0 ns:film.writer.film M1 .
?x0 ns:film.writer.film M2
}