proposition: Lemma isaset_disp_nat_trans {C' C : category} {D' : disp_cat C'} {D : disp_cat C} {x y : functor C' C} (f : nat_trans x y) (xx : disp_functor x D' D) (yy : disp_functor y D' D) : isaset (disp_nat_trans f xx yy).
proof: Proof. intros. simpl in *. apply (isofhleveltotal2 2). * do 2 (apply impred; intro). apply homsets_disp. * intro d. do 6 (apply impred; intro). apply hlevelntosn. apply homsets_disp. Qed.
imports: UniMath.Foundations.Sets UniMath.MoreFoundations.PartA UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.whiskering UniMath.CategoryTheory.FunctorCategory UniMath.CategoryTheory.DisplayedCats.Core UniMath.CategoryTheory.DisplayedCats.Functors UniMath.CategoryTheory.DisplayedCats.Isos