centos - -bash: /usr/bin/yum: /usr/bin/python2.6: bad interpreter: 不是目录

想升级下软件
yum -y update xxxxxxxx
得到这这个信息

-bash: /usr/bin/yum: /usr/bin/python2.6: bad interpreter: 不是目录

网上找过教程
照做了，但是不是行
我先查看了python

# whereis python

python: /usr/bin/python2.6 /usr/bin/python /usr/lib/python2.6 /usr/local/bin/python2.7-config /usr/local/bin/python2.7 /usr/local/bin/python /usr/local/lib/python2.7 /usr/include/python2.6 /usr/share/man/man1/python.1.gz

装了两个
修改了
/usr/bin/yum
改成了#!/usr/bin/python2.6
还是出-bash: /usr/bin/yum: /usr/bin/python2.6: bad interpreter: 不是目录
现在我不知道怎么整了
/usr/bin下有
python2.6
python2.6.6
还有一个python
....
升级python的时候做过ln -s /usr/local/bin/python2.7 /usr/bin/python