import gradio as gr

def dropdownbx(first, second):
    return f"selected_option_1st, {first}! selected_option_2nd {second}."

name_dropdown = gr.inputs.Dropdown(choices=["A1", "A2", "A3"], label="first")
city_dropdown = gr.inputs.Dropdown(choices=["aa1", "aa11", "aa2" , "aa22"], label="second")

output_text = gr.outputs.Textbox()

gr.Interface(fn=dropdownbx, inputs=[name_dropdown, city_dropdown], outputs=output_text).launch()