大家 在 import salt 时，可能会报错，no module named salt
这时候可以pip install salt
但是可能会报错 SNIMissingWarning: An HTTPS request has been made, but the SNI (Subject Name Indication) extension to TLS is not available on this platform.
解决办法： pip install pyopenssl ndg-httpsclient pyasn1
截至接续pip install salt ，可能还会报tornado requires an up-to-date SSL module
解决办法：pip install 'Tornado>=4.0.0,<5.0.0'
接下来可能会报找不到gcc
解决办法 yum -y install gcc
接下来还可能会报 command 'gcc' failed with exit status 1 while installing eventlet
解决办法 yum -y install python-devel
如果再不行的话，老哥，你肯定用的python2,7或者python3.5 了，请安装对应版本的python-devel吧，比如 pip install python3.5-devel
