proposition: Lemma ler_norm x : (x <= `|x|).
proof: Proof. exact: real_ler_norm. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(ssrAC div fintype path bigop order finset fingroup) mathcomp(ssralg poly)