question: Which American executive producer of M0 and M1 played M3 , M4 , M5 , and M6
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 ns:film.actor.film/ns:film.performance.character M3 .
  ?x0 ns:film.actor.film/ns:film.performance.character M4 .
  ?x0 ns:film.actor.film/ns:film.performance.character M5 .
  ?x0 ns:film.actor.film/ns:film.performance.character M6 .
  ?x0 ns:film.producer.films_executive_produced M0 .
  ?x0 ns:film.producer.films_executive_produced M1 .
  ?x0 ns:people.person.nationality ns:m.09c7w0
  }