question: Was M3 edited by a film editor that M1 and M2 employed and directed by M4
query: SELECT count(*) WHERE {
  ?x0 a ns:film.editor .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
  M3 ns:film.film.directed_by M4 .
  M3 ns:film.film.edited_by ?x0
  }