∀ {C : Type u_2} [inst : CategoryTheory.Category.{u_1, u_2} C] [inst_1 : CategoryTheory.MonoidalCategory C] (X : C),
  (CategoryTheory.MonoidalCategoryStruct.leftUnitor ((CategoryTheory.Functor.diag C).obj X)).hom =
    CategoryTheory.CategoryStruct.comp
      (CategoryTheory.MonoidalCategoryStruct.whiskerRight
        (CategoryTheory.Iso.refl (CategoryTheory.MonoidalCategoryStruct.tensorUnit (C × C))).hom
        ((CategoryTheory.Functor.diag C).obj X))
      (CategoryTheory.CategoryStruct.comp
        (CategoryTheory.Iso.refl
            (CategoryTheory.MonoidalCategoryStruct.tensorObj
              ((CategoryTheory.Functor.diag C).obj (CategoryTheory.MonoidalCategoryStruct.tensorUnit C))
              ((CategoryTheory.Functor.diag C).obj X))).hom
        ((CategoryTheory.Functor.diag C).map (CategoryTheory.MonoidalCategoryStruct.leftUnitor X).hom))