• Ensure you have these installed and accessible from the notebook pyngrok, nest_asyncio, fastapi, uvicorn and other libs you want

%pip install pyngrok nest_asyncio fastapi uvicorn loguru

• Create a FastAPI app

from fastapi import FastAPI
from pydantic import BaseModel
from loguru import logger

app = FastAPI()

class UserRequestIn(BaseModel):
    text: str
    
@app.post("/test")
def index(request: UserRequestIn):
    logger.debug(request)
    return {"ok": True}

• Start ngrok tunnel

import nest_asyncio
from pyngrok import ngrok
import uvicorn

ngrok_tunnel = ngrok.connect(8000)

ngrok_tunnel

• Patch Event Loop and start server

nest_asyncio.apply()
uvicorn.run(app, port=8000)

• Click on the ngrok url, and visit /docs and you will have the Swagger/OpenAPI page and call your api's from there