old_contents: bind = '127.0.0.1:8001'
  workers = 2
  worker_class = 'gevent'
  timeout = 30
  keepalive = 2
  errorlog = '-'
  
new_contents: workers = 2
  worker_class = 'gevent'
  timeout = 30
  keepalive = 2
  errorlog = '-'
  
subject: Use IP and PORT environment variables if set