python中的一个十分好用的包管理工具python-pip是我们使用python必不可少的一件工具。但是在CentOS7安装时候却报Error: Nothing to do：
[root@bnsf-lys ~]# pip
-bash: pip: command not found
[root@bnsf-lys ~]# yum install -y pip
Loaded plugins: langpacks, versionlock
Excluding update due to versionlock (use "yum versionlock status" to show it)
No package pip available.
Error: Nothing to do
[root@bnsf-lys ~]#
是因为CentOS官方的源有些时候滞后导致的。所以我们可以用fedora社区打造的EPEL(http://fedoraproject.org/wiki/EPEL)来进行安装即可：
[root@bnsf-lys ~]# yum -y install epel-release
[root@bnsf-lys ~]# yum -y install python-pip
[root@bnsf-lys ~]# pip --helpUsage:
pip <command> [options]Commands:
install Install packages.
download Download packages.
uninstall Uninstall packages.
freeze Output installed packages in requirements format.
list List installed packages.
show Show information about installed packages.
search Search PyPI for packages.
wheel Build wheels from your requirements.
hash Compute hashes of package archives.
completion A helper command used for command completion
help Show help for commands
