app.py

import gradio as gr
import spaces
import torch

zero = torch.Tensor([0]).cuda()
print(zero.device) # <-- 'cpu' 🤔

@spaces.GPU
def chat(prompt):
    print(zero.device) # <-- 'cuda:0' 🤗
    return f"Hello {zero + n} Tensor"

gr.Interface(
    fn=chat, 
    inputs=gr.Text(), 
    outputs=gr.Text()
).launch()