question: Which film editor was employed by M3 's employer , employed by a production company , and employed by M1 and M2
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 ?x2 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
  ?x1 ns:business.employer.employees/ns:business.employment_tenure.person M3 .
  ?x2 a ns:film.production_company
  }