∀ {C : Type u} [inst : CategoryTheory.Category.{v, u} C] {M : Type u_1} [inst_1 : CategoryTheory.Category.{v_1, u_1} M]
  [inst_2 : CategoryTheory.MonoidalCategory M] (F : CategoryTheory.Functor M (CategoryTheory.Functor C C)) {X Y : C}
  (f : X ⟶ Y) [inst_3 : F.OplaxMonoidal],
  CategoryTheory.CategoryStruct.comp ((CategoryTheory.Functor.OplaxMonoidal.η F).app X)
      ((CategoryTheory.MonoidalCategoryStruct.tensorUnit (CategoryTheory.Functor C C)).map f) =
    CategoryTheory.CategoryStruct.comp ((CategoryTheory.Functor.OplaxMonoidal.η F).app X) f