question: Was a actor that M0 's sequel was written by and starred M1
query: SELECT count(*) WHERE {
  ?x0 ns:film.film.prequel M0 .
  M1 a ns:film.actor .
  M1 ns:film.actor.film/ns:film.performance.film ?x0 .
  M1 ns:film.writer.film ?x0
  }