Lemma isaset_z_iso {C : category} (a b : ob C) : isaset (z_iso a b). Proof. change isaset with (isofhlevel 2). apply isofhleveltotal2. - apply homset_property. - intro f. apply isasetaprop. apply isaprop_is_z_isomorphism. Qed.
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.