python selenium+unittest 自动化测试

HTTPConnectionPool(host=u'127.0.0.1', port=51273): Max retries exceeded with url: /session/555b0eace718c79a338c24a9507421bd/url (Caused by NewConnectionError('<urllib3.connection.httpconnection at="" object="" style="font&#45;family&#58; &#34;Trebuchet MS&#34;&#44; Arial&#44; Helvetica&#44; sans&#45;serif&#59; font&#45;size&#58; medium&#59; white&#45;space&#58; normal&#59;">: Failed to establish a new connection: [Errno 10061] ',))</urllib3.connection.httpconnection>

<urllib3.connection.httpconnection at="" object="" style="font&#45;family&#58; &#34;Trebuchet MS&#34;&#44; Arial&#44; Helvetica&#44; sans&#45;serif&#59; font&#45;size&#58; medium&#59; white&#45;space&#58; normal&#59;">偶尔出现的异常信息，这个是什么意思</urllib3.connection.httpconnection>