Was a person that M1 was produced by , edited by , and executive produced by a British editor of M3
SELECT count(*) WHERE {
?x0 a ns:people.person .
?x0 ns:film.editor.film M1 .
?x0 ns:film.editor.film M3 .
?x0 ns:film.producer.films_executive_produced M1 .
?x0 ns:film.producer.film|ns:film.production_company.films M1 .
?x0 ns:people.person.nationality ns:m.07ssc
}