∀ {B : Type u₁} [inst : CategoryTheory.Bicategory B] {C : Type u₂} [inst_1 : CategoryTheory.Bicategory C]
  {F G : CategoryTheory.OplaxFunctor B C} {η θ : F ⟶ G} (Γ : CategoryTheory.Oplax.LaxTrans.Modification η θ) {a b : B}
  {a' : C} (f : a ⟶ b) (g : G.obj b ⟶ a') {Z : F.obj a ⟶ a'}
  (h : CategoryTheory.CategoryStruct.comp (CategoryTheory.CategoryStruct.comp (F.map f) (θ.app b)) g ⟶ Z),
  CategoryTheory.CategoryStruct.comp
      (CategoryTheory.Bicategory.whiskerRight (CategoryTheory.Bicategory.whiskerRight (Γ.app a) (G.map f)) g)
      (CategoryTheory.CategoryStruct.comp (CategoryTheory.Bicategory.whiskerRight (θ.naturality f) g) h) =
    CategoryTheory.CategoryStruct.comp (CategoryTheory.Bicategory.whiskerRight (η.naturality f) g)
      (CategoryTheory.CategoryStruct.comp
        (CategoryTheory.Bicategory.whiskerRight (CategoryTheory.Bicategory.whiskerLeft (F.map f) (Γ.app b)) g) h)