小编win*_*ain的帖子

我是龙卷风的新手,所以我按照龙卷风的指导练习,当我来使用Coroutines时,例子说:来自龙卷风进口gen

@gen.coroutine
def fetch_coroutine(url):
    http_client = AsyncHTTPClient()
    response = yield http_client.fetch(url)
    # In Python versions prior to 3.3, returning a value from
    # a generator is not allowed and you must use
    #   raise gen.Return(response.body)
    # instead.
    return response.body

当我运行这个测试时,它会在发生器内部引发语法错误'return',所以我取消注释建议,如下所示:import tornado.httpserver import tornado.ioloop import tornado.options import tornado.web

from tornado.options import define, options

define("port", default=8888, help="run on the given port", type=int)
from tornado import gen
from tornado.httpclient import AsyncHTTPClient

@gen.coroutine
def fetch_coroutine(url):
    http_client = AsyncHTTPClient()
    response = …