∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] [inst_1 : CategoryTheory.MonoidalCategory C] {X Y Z : C}
  (f : CategoryTheory.MonoidalCategoryStruct.tensorUnit C ⟶ Y) (g : X ⟶ Z),
  CategoryTheory.CategoryStruct.comp (CategoryTheory.MonoidalCategoryStruct.leftUnitor X).inv
      (CategoryTheory.MonoidalCategoryStruct.tensorHom f g) =
    CategoryTheory.CategoryStruct.comp g
      (CategoryTheory.CategoryStruct.comp (CategoryTheory.MonoidalCategoryStruct.leftUnitor Z).inv
        (CategoryTheory.MonoidalCategoryStruct.whiskerRight f Z))