Definition associator_is_natiso {C : category} {T : tensor_data C} (α : associator_data T) : UU := ∏ (x y z : C), is_z_isomorphism (α x y z).
Require Import UniMath.Foundations.All. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.CategoryTheory.Core.Isos.