https://blog.csdn.net/buki26/article/details/85004675

ConnectionError: HTTPConnectionPool(host=‘xxx.xx.xxx.xxx’, port=xxxx): Max retries exceeded with url: /api/v1/login/ (Caused by NewConnectionError(’<urllib3.connection.HTTPConnection object at 0x7f7c98a867d0>: Failed to establish a new connection: [Errno 111] Connection refused’,))
提示说请求太频繁，查阅资料有方法说用sleep，但是并没有解决我遇到的这种问题，最后解决办法是：
关闭多余的连接

s = requests.session()
s.keep_alive = False