app/fetch.py

import aiohttp


class Fetcher:
    def __init__(self):
        self.session = None

    async def start(self):
        if not self.session:
            self.session = aiohttp.ClientSession()

    async def stop(self):
        if self.session:
            await self.session.close()
            self.session = None

    async def fetch(self, url: str):
        async with self.session.get(url, timeout=30) as resp:
            text = await resp.text()
            return {"ok": True, "status": resp.status, "data": text}