question: Which film director that edited M1 and M2 was employed by M3 , employed by a production company , and employed by M4
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.director .
  ?x0 ns:film.editor.film M1 .
  ?x0 ns:film.editor.film M2 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company ?x1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M3 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M4 .
  ?x1 a ns:film.production_company
  }