官方例子:

from tornado.concurrent import Future

def async_fetch_future(url):
http_client = AsyncHTTPClient()
my_future = Future()
fetch_future = http_client.fetch(url)
fetch_future.add_done_callback(
lambda f: my_future.set_result(f.result()))
return my_future

什么协程,异步迷迷糊糊的!

完全不懂my_future = Future()为什么要生成个Future对象,最后又返回它！！已经痛苦了几天了！！大神来解救下我吧