fact: Definition unique_image_to_is_z_iso_in_REL {X Y : hSet} (r : bin_hrel X Y) : (∏ x: X, ∃! y : Y, r x y) × (∏ y : Y, ∃! x : X, r x y) -> is_z_isomorphism (C := REL) r.
imports: UniMath.Foundations.All UniMath.MoreFoundations.All UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.Categories.HSET.All