proposition: Fact total : total (<=%O : rel (T * T')).
proof: Proof. move=> x y; rewrite /<=%O /= /le; case: ltgtP => //= _; exact: le_total. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)