∀ {B : Type u₁} [inst : CategoryTheory.Bicategory B] {C : Type u₂} [inst_1 : CategoryTheory.Bicategory C]
  (F : CategoryTheory.Pseudofunctor B C) {a b : B} (f : a ⟶ b) {Z : F.obj a ⟶ F.obj b}
  (h : CategoryTheory.CategoryStruct.comp (F.map f) (F.map (CategoryTheory.CategoryStruct.id b)) ⟶ Z),
  CategoryTheory.CategoryStruct.comp (F.mapComp f (CategoryTheory.CategoryStruct.id b)).hom h =
    CategoryTheory.CategoryStruct.comp (F.map₂ (CategoryTheory.Bicategory.rightUnitor f).hom)
      (CategoryTheory.CategoryStruct.comp (CategoryTheory.Bicategory.rightUnitor (F.map f)).inv
        (CategoryTheory.CategoryStruct.comp (CategoryTheory.Bicategory.whiskerLeft (F.map f) (F.mapId b).inv) h))