Was M3 a production company whose British founder edited M0 and edited M1
SELECT count(*) WHERE {
?x0 ns:film.editor.film M0 .
?x0 ns:film.editor.film M1 .
?x0 ns:people.person.nationality ns:m.07ssc .
M3 a ns:film.production_company .
M3 ns:organization.organization.founders ?x0
}