∀ {C : Type u_2} [inst : CategoryTheory.Category.{u_1, u_2} C] [inst_1 : CategoryTheory.MonoidalCategory C],
  CategoryTheory.CategoryStruct.comp (CategoryTheory.Functor.OplaxMonoidal.η (CategoryTheory.Functor.id C))
      (CategoryTheory.Functor.LaxMonoidal.ε (CategoryTheory.Functor.id C)) =
    CategoryTheory.CategoryStruct.id
      ((CategoryTheory.Functor.id C).obj (CategoryTheory.MonoidalCategoryStruct.tensorUnit C))