text: import logging;logging.basicConfig(level=logging.INFO)
  import asyncio,os,json,time
  from datetime import datetime
  from aiohttp import web
  
  def index(request):
      return web.Response(body=b'<html><h1>welcome</h1></html>',content_type='text/html')
  
  @asyncio.coroutine
  def init(loop):
      app = web.Application(loop=loop)
      app.router.add_route('GET','/',index)
      ser = yield from loop.create_server(app.make_handler(),'127.0.0.1',9000)
      logging.info('server started at http://127.0.0.1:9000')
      return ser
  
  loop=asyncio.get_event_loop()
  loop.run_until_complete(init(loop))
  loop.run_forever()