查看系统当前python版本
2: [root@wangyuelou ~]# python
  1:  
  3: Python 2.4.3 (#1, May  5 2011, 16:39:10)
  4: [GCC 4.1.2 20080704 (Red Hat 4.1.2-50)] on linux2
  5: Type "help", "copyright", "credits" or "license" for more information.
  6: >;>>
  7: [root@wangyuelou ~]#
下载新版本的python
1: [root@wangyuelou ~]# wget http://python.org/ftp/python/2.7.2/Python-2.7.2.tgz
解压缩 以及编译
  1: [root@wangyuelou ~]# tar xvf Python-2.7.2.tar.bz2
  2: [root@wangyuelou Python-2.7.2]# ./configure --prefix=/usr/local/python27
  3: [root@wangyuelou Python-2.7.2]# make
  4: [root@wangyuelou Python-2.7.2]# make install
  5: [root@wangyuelou Python-2.7.2]# ls /usr/local/python27/ -al
  6: total 28
  7: drwxr-xr-x  6 root root 4096 Jul 14 00:21 .
  8: drwxr-xr-x 20 root root 4096 Jul 14 00:17 ..
  9: drwxr-xr-x  2 root root 4096 Jul 14 00:21 bin
 10: drwxr-xr-x  3 root root 4096 Jul 14 00:21 include
 11: drwxr-xr-x  4 root root 4096 Jul 14 00:21 lib
 12: drwxr-xr-x  3 root root 4096 Jul 14 00:21 share
覆盖原来的python链接
  1: [root@wangyuelou Python-2.7.2]# mv /usr/bin/python /usr/bin/python_old
  2: [root@wangyuelou Python-2.7.2]# ln -s /usr/local/python27/bin/python /usr/bin/
  3: [root@wangyuelou Python-2.7.2]# python
  4: Python 2.7.2 (default, Jul 14 2011, 00:20:14)
  5: [GCC 4.1.2 20080704 (Red Hat 4.1.2-50)] on linux2
  6: Type "help", "copyright", "credits" or "license" for more information.
  7: >>>
此处已经可以正常使用python2.7了
但是因为yum是使用的2.4的版本来用的，所以 还需要修改一下
  1: [root@wangyuelou ~]# yum
  2: There was a problem importing one of the Python modules
  3: required to run yum. The error leading to this problem was:
  4:  
  5:    No module named yum
  6:  
  7: Please install a package which provides this module, or
  8: verify that the module is installed correctly.
  9:  
 10: It's possible that the above module doesn't match the
 11: current version of Python, which is:
 12: 2.7.2 (default, Jul 14 2011, 00:20:14)
 13: [GCC 4.1.2 20080704 (Red Hat 4.1.2-50)]
 14:  
 15: If you cannot solve this problem yourself, please go to
 16: the yum faq at:
 17:   http://wiki.linux.duke.edu/YumFaq
 18:  
 19:  
 20: [root@wangyuelou Python-2.7.2]# vim /usr/bin/yum
 21:  
 22: #!/usr/bin/python   #修改此处为2.4的位置
 23: [root@wangyuelou ~]# vim /usr/bin/yum
 24:  
 25: #!/usr/bin/python2.4
 26: [root@wangyuelou ~]# yum
 27: Loaded plugins: fastestmirror
 28: You need to give some command
 29: usage: yum [options] COMMAND
 30:  
 31: List of Commands:
 32:  
 33: check-update   Check for available package updates
 34: clean          Remove cached data
 35: deplist        List a package's dependencies
 36: downgrade      downgrade a package
 37: erase          Remove a package or packages from your system
 38: groupinfo      Display details about a package group
 39: groupinstall   Install the packages in a group on your system
 40: grouplist      List available package groups
 41: groupremove    Remove the packages in a group from your system
 42: help           Display a helpful usage message
 43: info           Display details about a package or group of packages
 44: install        Install a package or packages on your system
 45: list           List a package or groups of packages
 46: localinstall   Install a local RPM
yum 又可以使用了