問題
pip3升級(jí)后啥箭，執(zhí)行 pip 會(huì)出現(xiàn)如下提示：
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/__init__.py:83: RequestsDependencyWarning: Old version of cryptography ([1, 2, 3]) may cause slowdown.
warnings.warn(warning, RequestsDependencyWarning)
pip 19.1.1 from /home/rogn/.local/lib/python2.7/site-packages/pip (python 2.7)
解法
1. 升級(jí) cryptography
sudo pip install --upgrade cryptography
2. 重新綁定pyOpenSSL（否則會(huì)出現(xiàn)：AttributeError: 'module' object has no attribute 'SSL_ST_INIT'）
sudo python3 -m easy_install --upgrade pyOpenSSL
