proposition: Lemma CoequalizerArrowisEpi {y z : C} {f g : y --> z} (E : Coequalizer f g ) : isEpi (CoequalizerArrow E).
proof: Proof. apply make_isEpi. intros z0 g0 h X. apply (CoequalizerOutsEq E). apply X. Qed.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.Epis UniMath.CategoryTheory.Limits.BinCoproducts UniMath.CategoryTheory.Retracts