question: Was M0 a Mexican art director that edited M2 and edited M3
query: SELECT count(*) WHERE {
  M0 a ns:film.film_art_director .
  M0 ns:film.editor.film M2 .
  M0 ns:film.editor.film M3 .
  M0 ns:people.person.nationality ns:m.0b90_r
  }