Lemma identity_is_z_iso {C : precategory} (a : ob C) : is_z_isomorphism (identity a). Proof. exists (identity a). simpl; split; apply id_left. Defined.
Require Import UniMath.Foundations.PartA. Require Import UniMath.Foundations.Propositions. Require Import UniMath.Foundations.Sets. Require Import UniMath.MoreFoundations.Tactics. Require Import UniMath.CategoryTheory.Core.Categories.