proposition: Lemma CokernelArrowisEpi {y z : C} {g : y --> z} (CK : Cokernel g ) : isEpi (CokernelArrow CK).
proof: Proof. unfold isEpi. intros z0 g0 h X. use CokernelOutsEq. exact X. 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