Lemma rwhisker_vcomp_CAT {C D E : category} (F G H : [C, D]) (I : [D, E]) (α : [C, D]⟦F, G⟧) (β : [C, D]⟦G, H⟧) : rwhisker_CAT I α · rwhisker_CAT I β = rwhisker_CAT I (α · β). Proof. apply pathsinv0, post_whisker_composition. Qed.
Require Import UniMath.Foundations.PartD. Require Import UniMath.MoreFoundations.Tactics. Require Import UniMath.CategoryTheory.Core.Categories. Require Import UniMath.CategoryTheory.Core.Functors. Require Import UniMath.CategoryTheory.Core.Isos. Require Import UniMath.CategoryTheory.Core.NaturalTransformations. Require Import UniMath.CategoryTheory.FunctorCategory. Require Import UniMath.CategoryTheory.whiskering.