前置条件：
python 2.5+
pycrypto 2.1+
安装readline-devel
sudo yum install readline-devel（解决centos下Python2.7交互模式中方向键、退格键乱码问题）
安装zlib-devel
sudo yum install zlib-devel(解决paramiko对zlib模块的依赖)
安装python
tar -xzvf Python-2.7.5.tgz
cd Python-2.7.5
安装pycrypto
tar -xzvf pycrypto-2.6.tar.gz
cd pycrypto-2.6
python setup.py build
python setup.py install
安装paramiko
unzip paramiko-1.10.zip
cd paramiko-1.10
python2.7 setup.py build
python setup.py install