app.py

import gradio as gr

with gr.Blocks() as demo:
    date_picker = gr.HTML("""<input type = "date" id = "date" name = "date">""")
    submit_btn = gr.Button(label = "Run")
    output = gr.Textbox()

    submit_btn.click(None, None, output, _js='(output) => {return (document.getElementById("date")).value;}')
    

demo.queue()
demo.launch(debug = True, share = False)