proposition: Lemma israpbinop_op : ∏ x y y' : X, op x y ≠ op x y' -> y ≠ y'.
proof: Proof. intros x y y'. now apply (pr2 (pr2 (pr2 X))). Qed.
imports: UniMath.Algebra.BinaryOperations UniMath.Foundations.Propositions UniMath.MoreFoundations.Sets UniMath.MoreFoundations.Tactics UniMath.MoreFoundations.DecidablePropositions