fact: Definition z_iso_to_iso {C : precategory} {b c : C} (f : z_iso b c) : iso b c := pr1 f ,, is_iso_from_is_z_iso (pr1 f) (pr2 f).
imports: UniMath.Foundations.PartA UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.MoreFoundations.Tactics UniMath.CategoryTheory.Core.Categories