proposition: Lemma isaprop_isZero (b : C) : isaprop (isZero b).
proof: Proof. apply isapropdirprod. - apply impred. intros t. apply isapropiscontr. - apply impred. intros t. apply isapropiscontr. Qed.
imports: UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.opp_precat UniMath.CategoryTheory.Limits.Initial UniMath.CategoryTheory.Limits.Terminal