∀ {J : Type u_4} [inst : CategoryTheory.Category.{u_3, u_4} J] {C : Type u_2}
  [inst_1 : CategoryTheory.Category.{u_1, u_2} C] (F : CategoryTheory.Functor J C)
  [inst_2 : CategoryTheory.Limits.HasColimit F] {X Y : J} (f : X ⟶ Y),
  CategoryTheory.CategoryStruct.comp (F.map f)
      (CategoryTheory.CostructuredArrow.mk (CategoryTheory.Limits.colimit.ι F Y)).hom =
    (CategoryTheory.CostructuredArrow.mk (CategoryTheory.Limits.colimit.ι F X)).hom