请教centos6.5 两个版本python共存问题

我有一台阿里云ces，系统是centos6.5 里面本身带了python 2.6.6， 后来我在里面有安装了python3.3.6
安装命令如下：
./configure --prefix=/usr/local/
make && make install

之后我安装了一些库，如：paramiko之类，但当我运行程序时出现如下错误：

 import paramiko
  File "<frozen importlib._bootstrap>", line 1565, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1532, in _find_and_load_unlocked
  File "/usr/local/lib/python3.3/site-packages/paramiko-2.0.1-py3.3.egg/paramiko/__init__.py", line 30, in <module>
  File "<frozen importlib._bootstrap>", line 1565, in _find_and_load
  File "<frozen importlib._bootstrap>", line 1532, in _find_and_load_unlocked
  File "/usr/local/lib/python3.3/site-packages/paramiko-2.0.1-py3.3.egg/paramiko/transport.py", line 32, in <module>
  File "/usr/local/lib/python3.3/site-packages/cryptography-1.4-py3.3-linux-x86_64.egg/cryptography/hazmat/backends/__init__.py", line 7, in <module>
    import pkg_resources
  File "/usr/local/lib/python3.3/site-packages/pkg_resources.py", line 45
    def _bypass_ensure_directory(name, mode=0777):

请教这个是怎么回事，如何解决？

def _bypass_ensure_directory(name, mode=0777):

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建议使用virtualenv

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已经解决是easy_install 安装的有问题，重新安装后就好了