question: Did M2 and M3 star a female person
query: SELECT count(*) WHERE {
  ?x0 a ns:people.person .
  ?x0 ns:people.person.gender ns:m.02zsn .
  M2 ns:film.film.starring/ns:film.performance.actor ?x0 .
  M3 ns:film.film.starring/ns:film.performance.actor ?x0
  }