proposition: Lemma mmorph1 : f 1%M = 1.
proof: Proof. exact: mmorphism_subproof.2. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq path choice finset fintype finfun) mathcomp(tuple bigop ssralg ssrint ssrnum) xfinmap