new_contents: #coding=utf8 
  from gevent import monkey; monkey.patch_all()
  import gevent
  import urllib2
  
  def f(url):
      print('GET: %s' % url)
      resp = urllib2.urlopen(url)
      data = resp.read()
      print('%d bytes received from %s.' % (len(data), url))
  
  gevent.joinall([
          gevent.spawn(f, 'https://www.python.org/'),
          gevent.spawn(f, 'https://www.yahoo.com/'),
          gevent.spawn(f, 'https://github.com/'),
  ])
subject: add gevent example