python-3.x - : NotImplementedError发生了异常

Question

第一次执行此操作，并在app.listen(port)处获取异常

import tornado.web
import tornado.ioloop

class basicRequestHandler(tornado.web.RequestHandler):
    def get(self):
        self.write("Hello, World this is a python command executed from the  backend.")

if __name__ == "__main__":
    app = tornado.web.Application([
        (r"/", basicRequestHandler)
    ])

    port = 8882
    app.listen(port)#Getting exception here 
    print(f"Application is ready and listening on port {port}")
    tornado.ioloop.IOLoop.current().start()

Answer 1

在python 3.8中:

import tornado.ioloop
import tornado.web
import asyncio

class basicRequestHandler(tornado.web.RequestHandler):
    def get(self):
        self.write("Hello, World this is a python command executed from the  backend.")

if __name__ == "__main__":
    asyncio.set_event_loop_policy(asyncio.WindowsSelectorEventLoopPolicy())
    app = tornado.web.Application([
    (r"/", basicRequestHandler)
    ])
    port = 8882
    app.listen(port)
    print(f"Application is ready and listening on port {port}")
    tornado.ioloop.IOLoop.current().start()