Lemma opp_ShortShortExactData_Eq {C : category} {Z : Zero C} (SSED : ShortShortExactData (op_category C) (Zero_opp C Z)) : Mor1 (opp_MorphismPair SSED) · Mor2 (opp_MorphismPair SSED) = ZeroArrow Z (Ob1 (opp_MorphismPair SSED)) (Ob3 (opp_MorphismPair SSED)). Proof. use (pathscomp0 (@ShortShortExactData_Eq (op_category C) (Zero_opp C Z) SSED)). rewrite <- ZeroArrow_opp. apply idpath. Qed.
Require Import UniMath.Foundations.PartD. Require Import UniMath.Foundations.Propositions. Require Import UniMath.Foundations.Sets. Require Import UniMath.MoreFoundations.Notations. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Isos. Require Import UniMath.CategoryTheory.opp_precat. Require Import UniMath.CategoryTheory.Limits.Zero. Require Import UniMath.CategoryTheory.Limits.Opp.