∀ {C : Type u_4} [inst : CategoryTheory.Category.{u_3, u_4} C] {X Y : C} (f g : X ⟶ Y) {D : Type u_2}
  [inst_1 : CategoryTheory.Category.{u_1, u_2} D] (G : CategoryTheory.Functor C D) {Z : C} {h : Y ⟶ Z},
  CategoryTheory.CategoryStruct.comp f h = CategoryTheory.CategoryStruct.comp g h →
    CategoryTheory.CategoryStruct.comp (G.map f) (G.map h) = CategoryTheory.CategoryStruct.comp (G.map g) (G.map h)