∀ {B : Type u_2} [inst : CategoryTheory.Bicategory B] {C : Type u_6} [inst_1 : CategoryTheory.Bicategory C]
  {F G : CategoryTheory.OplaxFunctor B C} (η : F ⟶ G) {a b : B} (f : a ⟶ b),
  CategoryTheory.CategoryStruct.comp
      (CategoryTheory.Bicategory.whiskerLeft (F.map f) (CategoryTheory.CategoryStruct.id (η.app b))) (η.naturality f) =
    CategoryTheory.CategoryStruct.comp (η.naturality f)
      (CategoryTheory.Bicategory.whiskerRight (CategoryTheory.CategoryStruct.id (η.app a)) (G.map f))