Definition is_z_isomorphism_inv {C : precategory_data} {a b : C} {f : a --> b} (I : is_z_isomorphism f) : is_z_isomorphism (is_z_isomorphism_mor I). Proof. use make_is_z_isomorphism. - exact f. - exact (is_inverse_in_precat_inv I). 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.