question: Was M0 a British film editor that M2 was written by and starred
query: SELECT count(*) WHERE {
  M0 a ns:film.editor .
  M0 ns:film.actor.film/ns:film.performance.film M2 .
  M0 ns:film.writer.film M2 .
  M0 ns:people.person.nationality ns:m.07ssc
  }