proposition: Lemma reduced_reduce s : reduced (reduce s).
proof: Proof. rewrite /reduced uniq_predom_reduce /=. by apply/allP=> zx; rewrite mem_filter=> /andP []. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop order generic_quotient) mathcomp(ssralg ssrnum ssrint)