app.py

import gradio as gr

global models_dict
models_dict = { 
   "RealVision": "SG161222/RealVisXL_V4.0" , 
   "Unstable": "stablediffusionapi/sdxl-unstable-diffusers-y"
}

def greet(name):
    return "Hello " + name + "!!"

iface = gr.Interface(fn=greet, inputs="text", outputs="text")
iface.launch()