question: What did a Spanish person executive produce and M0 executive produce
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 ns:film.film.executive_produced_by ?x1 .
  ?x0 ns:film.film.executive_produced_by M0 .
  ?x1 a ns:people.person .
  ?x1 ns:people.person.nationality ns:m.06mkj
  }