∀ {B : Type u} [inst : CategoryTheory.Bicategory B] {a b c d e : B} (f : a ⟶ b) (g : b ⟶ c) (h : c ⟶ d) (i : d ⟶ e)
  {Z : a ⟶ e}
  (h_1 :
    CategoryTheory.CategoryStruct.comp f
        (CategoryTheory.CategoryStruct.comp (CategoryTheory.CategoryStruct.comp g h) i) ⟶
      Z),
  CategoryTheory.CategoryStruct.comp
      (CategoryTheory.Bicategory.associator (CategoryTheory.CategoryStruct.comp f g) h i).inv
      (CategoryTheory.CategoryStruct.comp
        (CategoryTheory.Bicategory.whiskerRight (CategoryTheory.Bicategory.associator f g h).hom i)
        (CategoryTheory.CategoryStruct.comp
          (CategoryTheory.Bicategory.associator f (CategoryTheory.CategoryStruct.comp g h) i).hom h_1)) =
    CategoryTheory.CategoryStruct.comp
      (CategoryTheory.Bicategory.associator f g (CategoryTheory.CategoryStruct.comp h i)).hom
      (CategoryTheory.CategoryStruct.comp
        (CategoryTheory.Bicategory.whiskerLeft f (CategoryTheory.Bicategory.associator g h i).inv) h_1)