question: Was a film 's producer employed by M0 and M1 and employed by M2 and M3
query: SELECT count(*) WHERE {
  ?x0 ns:film.producer.film|ns:film.production_company.films ?x1 .
  ?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M0 .
  ?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
  }