Lemma is_invertible_2cell_lassociator {a b c d : C} (f : C⟦a,b⟧) (g : C⟦b,c⟧) (h : C⟦c,d⟧) : is_invertible_2cell (lassociator f g h). Proof. exists (rassociator f g h). split; [ apply lassociator_rassociator | apply rassociator_lassociator ]. Defined.
Require Import UniMath.Foundations.All. Require Import UniMath.MoreFoundations.All. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Isos. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.CategoryTheory.Core.NaturalTransformations. Require Import UniMath.CategoryTheory.PrecategoryBinProduct.