Lemma abgr_monic_kernel_in_hfiber_mult_eq {A B : abgr} (f : abgr_category⟦A, B⟧) (w : abgr) (x x' : w) (h : abgr_category⟦w, B⟧) (X : hfiber (pr1 f) (pr1 h x)) (X0 : hfiber (pr1 f) (pr1 h x')) : pr1 f (pr1 X * pr1 X0)%multmonoid = pr1 h (x * x')%multmonoid. Proof. rewrite (pr1 (pr2 f)). rewrite (pr2 X). rewrite (pr2 X0). rewrite (pr1 (pr2 h)). use idpath. Qed.
Require Import UniMath.Foundations.PartD. Require Import UniMath.Foundations.Propositions. Require Import UniMath.Foundations.Sets. Require Import UniMath.Foundations.UnivalenceAxiom. Require Import UniMath.Algebra.BinaryOperations. Require Import UniMath.Algebra.Groups. Require Import UniMath.Algebra.Monoids. Require Import UniMath.NumberSystems.Integers. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Isos. Require Import UniMath.CategoryTheory.Core.Univalence. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.CategoryTheory.Monics. Require Import UniMath.CategoryTheory.Epis. Require Import UniMath.CategoryTheory.CategoriesWithBinOps. Require Import UniMath.CategoryTheory.PrecategoriesWithAbgrops. Require Import UniMath.CategoryTheory.PreAdditive. Require Import UniMath.CategoryTheory.Additive. Require Import UniMath.CategoryTheory.Abelian. Require Import UniMath.CategoryTheory.Limits.Zero. Require Import UniMath.CategoryTheory.Limits.BinProducts. Require Import UniMath.CategoryTheory.Limits.BinCoproducts. Require Import UniMath.CategoryTheory.Limits.Equalizers. Require Import UniMath.CategoryTheory.Limits.Coequalizers. Require Import UniMath.CategoryTheory.Limits.Kernels. Require Import UniMath.CategoryTheory.Limits.Cokernels. Require Import UniMath.CategoryTheory.Limits.BinDirectSums. @ZeroArrowFrom abgr_category abgr_Zero A = abgrfunfromunit A.