2019年python 2/3异步

我必须同时保持我的应用程序与python 2和3兼容。

我有一些类似下面的代码,我希望能够异步调用一个函数,然后等待我的所有未来得到解决。

代码:

import requests

# This would return a future
def get_xhr(url):
    return requests.get('https://www.{}.com'.format(url))

# This would return an array of futures
def get_search_engines():
    urls = ['google', 'yahoo', 'bing']
    return [get_xhr(url) for url in urls]


# Here I want to wait for all the futures to be resolved
get_search_engines()

print('All requests are done')

asyncio async/await似乎只与python 3兼容。

什么是能够运行与两个Python2/3兼容的异步函数的最佳方法?