# -*- encoding: utf-8 -*-
"""
@Time    : 2020/6/29
@Author  : hongboli
"""
import asyncio


class AsyncContextManager:
    def __init__(self):
        self.conn = conn


async def do_something(self):
    # 异步操作数据库
    return 666


async def __aenter__(self):
    # 异步链接数据库
    self.conn = await asyncio.sleep(1)
    return self


async def __aexit__(self, exc_type, exc, tb):
    # 异步关闭数据库链接
    await asyncio.sleep(1)


async def func():
    async with AsyncContextManager() as f:
        result = await f.do_something()
        print(result)


asyncio.run(func())