python 通过get-pip.py 安装 pip时报错 ERROR: No matching distribution found for pip

执行python get-pip.py报错：

Could not fetch URL https://pypi.org/simple/pip/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host=‘pypi.org’, port=443): Max retries exceeded with url: /simple/pip/ (Caused by SSLError(“Can’t connect to HTTPS URL because the SSL module is not available.”)) - skipping
ERROR: Could not find a version that satisfies the requirement pip
ERROR: No matching distribution found for pip

更换镜像地址解决：
python3 get-pip.py -i http://pypi.douban.com/simple --trusted-host pypi.douban.com