proposition: Lemma CokernelOfZeroArrow_isCokernel (x y : C) : isCokernel (ZeroArrow Z x y) (identity y) (id_right (ZeroArrow Z x y)).
proof: Proof. use make_isCokernel. intros w h H'. use unique_exists. - exact h. - exact (id_left _). - intros y0. apply hs. - intros y0 t. cbn in t. rewrite id_left in t. exact t. Qed.
imports: UniMath.Foundations.PartD UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Epis UniMath.CategoryTheory.Limits.Coequalizers UniMath.CategoryTheory.Limits.Zero