question: Was M0 's Mexican executive producer employed by M1 and M2
query: SELECT count(*) WHERE {
  ?x0 ns:film.producer.films_executive_produced 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.nationality ns:m.0b90_r
  }