升级后yum无法使用，报错如下
File "/bin/yum", line 30
except KeyboardInterrupt, e:
^
SyntaxError: invalid syntax
File "/usr/libexec/urlgrabber-ext-down", line 28
except OSError, e:
^
SyntaxError: invalid syntax
解决方法
修改以下三个文件
/usr/bin/yum
/usr/libexec/urlgrabber-ext-down
/usr/bin/yum-config-manager
将开头的#!/usr/bin/python改为#!/usr/bin/python2.7