question: Which country of nationality of a art director and producer of M1 employed a film editor
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 ^ns:people.person.nationality ?x1 .
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x2 .
  ?x1 ns:film.film_art_director.films_art_directed M1 .
  ?x1 ns:film.producer.film|ns:film.production_company.films M1 .
  ?x2 a ns:film.editor
  }