SSLError(SSLEOFError(8, ‘EOF occurred in violation of protocol
Could not fetch URL https://pypi.douban.com/simple/redis/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.doubanio.com', port=443): Max retries exceeded with url: /simple/redis/ (Caused by SSLError(SSLEOFError(8, 'EOF occurred in violation of protocol (_ssl.c:1129)'))) - skipping
就是把系统代理关掉
或者搜索pip.ini文件
增加trusted-host = mirrors.aliyun.com
（这里是对应的host，也可能是douban之类的）