question: Was M1 employed by a film producer , employed by M2 , M3 , and M4 , and employed by M5 and M6
query: SELECT count(*) WHERE {
  ?x0 a ns:film.producer .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company ?x0 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M2 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M3 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M4 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M5 .
  M1 ns:people.person.employment_history/ns:business.employment_tenure.company M6
  }