proposition: Lemma isirreflapSet {X : apSet} : ∏ x : X, ¬ (x # x).
proof: Proof. exact (pr1 (pr2 (pr2 X))). Qed.
imports: UniMath.Algebra.BinaryOperations UniMath.Foundations.Propositions UniMath.MoreFoundations.Sets UniMath.MoreFoundations.Tactics UniMath.MoreFoundations.DecidablePropositions