question: Which film editor did a film distributor employ , M1 employ , M2 employ , and M3 employ
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:film.editor .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company ?x1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M3 .
  ?x1 a ns:film.film_distributor
  }