question: Which founder of a film producer produced M1 's sequel
query: SELECT DISTINCT ?x0 WHERE {
  ?x0 ns:film.producer.film|ns:film.production_company.films ?x1 .
  ?x0 ns:organization.organization_founder.organizations_founded ?x2 .
  ?x1 ns:film.film.prequel M1 .
  ?x2 a ns:film.producer
  }