∀ {B : Type u₁} [inst : CategoryTheory.Bicategory B] {C : Type u₂} [inst_1 : CategoryTheory.Bicategory C]
  {F G : CategoryTheory.LaxFunctor B C} (self : CategoryTheory.Lax.StrongTrans F G) (a : B) {Z : F.obj a ⟶ G.obj a}
  (h : CategoryTheory.CategoryStruct.comp (F.map (CategoryTheory.CategoryStruct.id a)) (self.app a) ⟶ Z),
  CategoryTheory.CategoryStruct.comp (CategoryTheory.Bicategory.whiskerLeft (self.app a) (G.mapId a))
      (CategoryTheory.CategoryStruct.comp (self.naturality (CategoryTheory.CategoryStruct.id a)).hom h) =
    CategoryTheory.CategoryStruct.comp (CategoryTheory.Bicategory.rightUnitor (self.app a)).hom
      (CategoryTheory.CategoryStruct.comp (CategoryTheory.Bicategory.leftUnitor (self.app a)).inv
        (CategoryTheory.CategoryStruct.comp (CategoryTheory.Bicategory.whiskerRight (F.mapId a) (self.app a)) h))