question: Which production company whose German employee executive produced M2 and M3 was M1 's producer
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.production_company .
  ?x0 ns:business.employer.employees/ns:business.employment_tenure.person ?x1 .
  ?x0 ns:film.producer.film|ns:film.production_company.films M1 .
  ?x1 ns:film.producer.films_executive_produced M2 .
  ?x1 ns:film.producer.films_executive_produced M3 .
  ?x1 ns:people.person.nationality ns:m.0345h
  }