∀ {B : Type u_1} [inst : CategoryTheory.Bicategory B] (self : CategoryTheory.LaxFunctor B CategoryTheory.Cat) {a b : B}
  (f : a ⟶ b) (X : ↑(self.obj a)),
  (self.map₂ (CategoryTheory.Bicategory.rightUnitor f).inv).toNatTrans.app X =
    CategoryTheory.CategoryStruct.comp ((self.mapId b).toNatTrans.app ((self.map f).toFunctor.obj X))
      ((self.mapComp f (CategoryTheory.CategoryStruct.id b)).toNatTrans.app X)