fact: Definition z_iso_comp {C : precategory} {a b c : C} (I1 : z_iso a b) (I2 : z_iso b c) : z_iso a c.
imports: UniMath.Foundations.PartA UniMath.Foundations.Propositions UniMath.Foundations.Sets UniMath.MoreFoundations.Tactics UniMath.CategoryTheory.Core.Categories