proposition: Lemma module_mult_1 {R : ring} {M : module R} (r : R) : r * unel M = unel M.
proof: Proof. exact (pr2 (pr2 (pr2module M r))). Defined.
imports: UniMath.MoreFoundations.Tactics UniMath.Algebra.RigsAndRings UniMath.Algebra.Groups UniMath.Algebra.Monoids