pip是python环境的包管理工具，用它可以方便地管理第三方包，其功能类似于Linux系统下的yum或apt-get。
常用命令：
To list all the options that pip can use:>>> pip --help
Search packages from the PyPi repository:>>> pip search package
Install PyPi packages(//by default, pip will install the latest version of packages):>>> pip install package
Specify the particular version of package you plan to install (//specific version): >>> pip install package==1.0.4
Check the detailed installed folders and files:>>> pip show --files package
Check which packages are out of date and need updating:>>> pip list --outdated
List out all the installed packages:>>> pip list
Update package:>>> pip install -U package or pip install --upgrade package
Remove package:>>> pip uninstall package