proposition: Fact le_refl : reflexive le.
proof: Proof. by move=> x; case: (le x x) (le_total x x). Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)