[root@localhost setuptools-3.3]# easy_install pip
Traceback (most recent call last):
  File "/usr/bin/easy_install", line 5, in 
    from pkg_resources import load_entry_point
  File "build/bdist.linux-i686/egg/pkg_resources.py", line 2749, in 
                    
  File "build/bdist.linux-i686/egg/pkg_resources.py", line 446, in _build_master
                    
  File "build/bdist.linux-i686/egg/pkg_resources.py", line 459, in _build_from_requirements
    is returned.
  File "build/bdist.linux-i686/egg/pkg_resources.py", line 628, in resolve
    error that occurred. Usually this will be a ``DistributionNotFound`` or
pkg_resources.DistributionNotFound: setuptools==0.9.6


因为之前的python版本为2.4的后来升级为2.7的，但是easy_install还是读取2.4的配置

所以要重新做个软连接

[root@localhost bin]# ln -s /usr/local/python2.7/bin/easy_install /usr/bin/easy_install
ln: 正在创建指向“/usr/local/python2.7/bin/easy_install”的符号链接“/usr/bin/easy_install”: 文件已存在
[root@localhost bin]# rm -rf /usr/bin/easy_install
[root@localhost bin]# ln -s /usr/local/python2.7/bin/easy_install /usr/bin/easy_install


ipython同样的原理，安装完ipython后无法使用，同样创个软连接

[root@localhost ipython-1.2.1]# ln -s /usr/local/python2.7/bin/ipython /usr/bin/ipython
[root@localhost ipython-1.2.1]# ipython
Python 2.7.6 (default, Feb 14 2014, 06:05:34)
Type "copyright", "credits" or "license" for more information.
IPython 1.2.1 -- An enhanced Interactive Python.
?         -> Introduction and overview of IPython's features.
%quickref -> Quick reference.
help      -> Python's own help system.
object?   -> Details about 'object', use 'object??' for extra details.
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