kle
            with open({:d}, "wb") as f:

                @(lambda x:x)  # Py 3.9
                def noop(x): return x

                a = (b := f'1{{2}}3') + noop('x')  # Py 3.8 (:=) / 3.6 (f'')

                async def foo(arg): return await arg  # Py 3.5

                pickle.dump(dict(a=a, b=b), f)
            rO