RuntimeError: Cannot run the event loop while another loop is running(目前没有解决)

代码如下: import tornado.ioloop import tornado.web from tornado.httpclient import HTTPClient, AsyncHTTPClient class MainHandler(tornado.web.RequestHandler): # 同步 def get(self): h_c = HTTPClient() res = h_c.fetch("http://www.baidu.com") # print(res) # pass