question: Was M1 a film whose writer directed , edited , and produced M0 's sequel
query: SELECT count(*) WHERE {
  ?x0 ns:film.director.film ?x1 .
  ?x0 ns:film.editor.film ?x1 .
  ?x0 ns:film.producer.film|ns:film.production_company.films ?x1 .
  ?x1 ns:film.film.prequel M0 .
  M1 a ns:film.film .
  M1 ns:film.film.written_by ?x0
  }