proposition: Lemma enum_set1 (a : T) : enum [set a] = [:: a].
proof: Proof. by rewrite enum_set1. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)