How to get the selected example using Example component?

When I click an example in the Example component, I want this action to trigger a function store_example_img(img). This function stores the selected image in gr.State(), so that I can obtain the original image in the following process. But I can’t obtain the selected example image anyway, store_example_img always gets None. My code shows the following (key code):

original_image = gr.State(value=None, interactive=True)   # store original image without points, default None
input_image = gr.Image(type="numpy")

example = gr.Examples(
            examples=[os.path.join(os.path.dirname(__file__), "./images/53960-scaled.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/2388455-scaled.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/1.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/2.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/3.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/4.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/5.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/6.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/7.jpg"),
                      os.path.join(os.path.dirname(__file__), "./images/8.jpg"),
                      ],
            inputs=input_image,
            outputs=output_image,
            fn=store_example_img,
            run_on_click=True,
        )

def store_example_img(img):
    return img

I’ve tried a lot of other ways, such as getting image via input_image.value in store_example_img, but still None. I am sure that store_example_img worked when the Example is clicked. I suspect fn is finished running before the image enters the input_image.