question: What employee of a film producer was a editor and producer of M0 and M1
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 ns:film.editor.film M0 .
  ?x0 ns:film.editor.film M1 .
  ?x0 ns:film.producer.film|ns:film.production_company.films M0 .
  ?x0 ns:film.producer.film|ns:film.production_company.films M1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company ?x1 .
  ?x1 a ns:film.producer
  }