∀ {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.LaxMonoidal],
  CategoryTheory.CategoryStruct.comp ((CategoryTheory.Functor.LaxMonoidal.ε F).app X)
      ((F.obj (CategoryTheory.MonoidalCategoryStruct.tensorUnit M)).map f) =
    CategoryTheory.CategoryStruct.comp f ((CategoryTheory.Functor.LaxMonoidal.ε F).app Y)