02_pip区别： linux环境下python2，python3的

1、pip与pip3理解

centos中，我的pip与pip3都是python2.7的，所以无法安装成功，总是安装成python2的

[root@IP ~]# pip -V
pip 19.1.1 from /usr/lib/python2.7/site-packages/pip-19.1.1-py2.7.egg/pip (python 2.7)
[root@IP ~]# pip3 -V
pip 19.1.1 from /usr/lib/python2.7/site-packages/pip-19.1.1-py2.7.egg/pip (python 2.7)

新的linux有些无pip，先安装pip

[root@IP ~]# yum install python3-pip -y

[root@IP ~]# yum install python2-pip -y

查看版本

[root@IP ~]# pip -V
pip 19.1.1 from /usr/lib/python2.7/site-packages/pip-19.1.1-py2.7.egg/pip (python 2.7)
[root@IP ~]# pip3 -V
pip 9.0.3 from /usr/lib/python3.6/site-packages (python 3.6)