`{Univalence} {A B B' : AbGroup} (f : B' $-> B) {E F : AbSES B A} (p : abses_path_data_iso E F) : ap (abses_pullback f) (equiv_path_abses_iso p) = equiv_path_abses_iso (fmap (abses_pullback f) p). Proof. refine (ap_abses_pullback _ _ @ _). apply (ap (equiv_path_abses_iso o _)). apply eissect. Defined.
Require Import Basics Types. Require Import HSet Limits.Pullback. Require Import WildCat Pointed.Core Homotopy.ExactSequence. Require Import Modalities.ReflectiveSubuniverse. Require Import AbGroups.AbelianGroup AbGroups.AbPullback AbGroups.Biproduct. Require Import AbSES.Core AbSES.DirectSum.