Was M1 's employee a film producer that M2 's prequel was written by and edited by
SELECT count(*) WHERE {
?x0 a ns:film.producer .
?x0 ns:film.editor.film ?x1 .
?x0 ns:film.writer.film ?x1 .
?x0 ns:people.person.employment_history/ns:business.employment_tenure.company M1 .
?x1 ns:film.film.sequel M2
}