proposition: Lemma mor_disp_transportf_postwhisker {C : precategory} {D : disp_cat_data C} {x y z : C} {f f' : x --> y} (ef : f = f') {g : y --> z} {xx : D x} {yy} {zz} (ff : xx -->[f] yy) (gg : yy -->[g] zz) : (transportf _ ef ff) ;; gg = transportf _ (cancel_postcomposition _ _ g ef) (ff ;; gg).
proof: Proof. destruct ef; apply idpath. Qed.
imports: UniMath.Foundations.Sets UniMath.Foundations.PartD UniMath.MoreFoundations.PartA UniMath.MoreFoundations.AxiomOfChoice UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.whiskering