Ubuntu pip版本的安装，卸载，查看，更新

pip版本的安装：

sudo apt-get install python3-pip

pip版本的查看：

pip3 --version


pip3 -V

pip更新：

sudo pip3 install --upgrade pip

pip卸载：

sudo apt-get remove python3-pip

pip3安装过后在查看版本的时候会出现这个问题

Original exception was:
Traceback (most recent call last):
  File "/usr/bin/pip3", line 9, in <module>
    from pip import main
ImportError: cannot import name 'main'

执行下面命令改变里面的文件即可

sudo vi /usr/bin/pip3

#!/usr/bin/python3
# GENERATED BY DEBIAN

import sys

# Run the main entry point, similarly to how setuptools does it, but because
# we didn't install the actual entry point from setup.py, don't use the
# pkg_resources API.
from pip import __main__
if __name__ == '__main__':
    sys.exit(__main__._main())