fact: Definition nattrans_nattrans_arrow_assoc {C:category} {c:C} {X X' X'':[C^op,HSET]} (x:c⇒X) (p:X-->X') (q:X'-->X'') : q ⟳ (p ⟳ x) = (q ∘ p) ⟳ x := idpath _.
imports: UniMath.CategoryTheory.Core.Categories UniMath.CategoryTheory.Core.Isos UniMath.CategoryTheory.Core.Functors UniMath.CategoryTheory.Core.NaturalTransformations UniMath.CategoryTheory.Core.Univalence UniMath.CategoryTheory.opp_precat UniMath.CategoryTheory.yoneda UniMath.CategoryTheory.Categories.HSET.Core UniMath.CategoryTheory.Categories.HSET.MonoEpiIso UniMath.Foundations.Preamble UniMath.Foundations.Sets UniMath.MoreFoundations.Tactics