Definition CokernelofZeroArrow_iso (x y : C) (CK : Cokernel (ZeroArrow Z x y)) : z_iso y CK := make_z_iso (CokernelArrow CK) (from_Cokernel_to_Cokernel CK (CokernelofZeroArrow x y)) (CokernelofZeroArrow_is_iso CK).
Require Import UniMath.Foundations.PartD. Require Import UniMath.Foundations.Propositions. Require Import UniMath.Foundations.Sets. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Isos. Require Import UniMath.CategoryTheory.Epis. Require Import UniMath.CategoryTheory.Limits.Coequalizers. Require Import UniMath.CategoryTheory.Limits.Zero. - exact (ZeroArrowFrom w). - intros y X. cbn in X. use ArrowsFromZero.