如何检查Pyppeteer浏览器是否已关闭？

import asyncio
from pyppeteer import launch

async def check_browser_closed():
    browser = await launch()
    # 执行一些操作
    is_closed = browser.is_closed()
    print(f"浏览器是否已关闭：{is_closed}")
    await browser.close()

asyncio.get_event_loop().run_until_complete(check_browser_closed())

import asyncio
from pyppeteer import launch

async def check_browser_closed():
    browser = await launch()
    # 执行一些操作
    ws_endpoint = browser.wsEndpoint
    is_closed = ws_endpoint is None
    print(f"浏览器是否已关闭：{is_closed}")
    await browser.close()

asyncio.get_event_loop().run_until_complete(check_browser_closed())