∀ {J : Type u_4} [inst : CategoryTheory.Category.{u_3, u_4} J] {C : Type u_6}
  [inst_1 : CategoryTheory.Category.{u_5, u_6} C] {D : Type u_2} [inst_2 : CategoryTheory.Category.{u_1, u_2} D]
  {F : CategoryTheory.Functor J C} {H H' : CategoryTheory.Functor C D} (α : H ≅ H') (c : CategoryTheory.Limits.Cone F)
  (j : J),
  (((CategoryTheory.Limits.Cones.functoriality F H).comp
                (CategoryTheory.Limits.Cones.postcompose (F.whiskerLeft α.hom))).obj
            c).π.app
      j =
    CategoryTheory.CategoryStruct.comp (α.app c.pt).hom
      (((CategoryTheory.Limits.Cones.functoriality F H').obj c).π.app j)