question: Who was employed by M1 , employed by a film producer , and employed by M2 , M3 , M4 , and M5
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 a ns:people.person .
  ?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 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M4 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M5 .
  ?x1 a ns:film.producer
  }