Was M1 a country of nationality of a editor and executive producer of a prequel of M0
SELECT count(*) WHERE {
?x0 ns:film.editor.film ?x1 .
?x0 ns:film.producer.films_executive_produced ?x1 .
?x1 ns:film.film.sequel M0 .
M1 ^ns:people.person.nationality ?x0
}