app.py

import gradio as gr
import open3d_zerogpu_fix
import open3d as o3d
import spaces

assert o3d.core.cuda.is_available() is False

@spaces.GPU
def greet(n):
    assert o3d.core.cuda.is_available() is True
    return o3d.core.Tensor([], device=o3d.core.Device("CUDA:0")).device

demo = gr.Interface(fn=greet, inputs=gr.Number(), outputs=gr.Text())
demo.launch()