Definition lassociator_fun {a b c d : C} (x : C⟦a,b⟧ × C⟦b,c⟧ × C⟦c,d⟧) : pr1 x · (pr12 x · pr22 x) ==> (pr1 x · pr12 x) · pr22 x := lassociator (pr1 x) (pr12 x) (pr22 x).
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.