app.py

from transformers import GPT2Tokenizer, GPT2Model
tokenizer = GPT2Tokenizer.from_pretrained('gpt2')
model = GPT2Model.from_pretrained('gpt2')
import gradio as gr

def gpt2(string):
    text = string
    encoded_input = tokenizer(text, return_tensors='pt')
    output = model(**encoded_input)
    return output

iface = gr.Interface(fn=gpt2, inputs="text", outputs="text")
iface.launch()