∀ (C : Type u_2) [inst : CategoryTheory.Category.{u_1, u_2} C] [inst_1 : CategoryTheory.MonoidalCategory C]
  {X Y : CategoryTheory.Comon C} (f : X ⟶ Y),
  CategoryTheory.CategoryStruct.comp CategoryTheory.MonObj.mul f.hom.op =
    CategoryTheory.CategoryStruct.comp (CategoryTheory.MonoidalCategoryStruct.tensorHom f.hom.op f.hom.op)
      CategoryTheory.MonObj.mul