python-dev 安装错误

/********************************************************************
 *                    python-dev 安装错误
 * 说明：
 *     今天在安装python相关开发工具的时候出现了这个错误。
 *
 *                                  2016-8-15 深圳 南山平山村 曾剑锋
 *******************************************************************/

一. 参考文档：
    1. Can‘t install python-dev
        http://askubuntu.com/questions/749552/cant-install-python-dev

二. 错误现象：
    root@workflow:/home# apt-get install python-dev
    Reading package lists... Done
    Building dependency tree       
    Reading state information... Done
    Some packages could not be installed. This may mean that you have
    requested an impossible situation or if you are using the unstable
    distribution that some required packages have not yet been created
    or been moved out of Incoming.
    The following information may help to resolve the situation:

    The following packages have unmet dependencies:
     python-dev : Depends: libpython-dev (= 2.7.9-1) but it is not going to be installed
                  Depends: python2.7-dev (>= 2.7.9-1~) but it is not going to be installed
    E: Unable to correct problems, you have held broken packages.

三. 解决办法：
    1. cat /etc/apt/sources.list
        ......
        deb http://cz.archive.ubuntu.com/ubuntu wily main
        ......
    2. sudo apt-get update
    3. apt-get install python-dev