转自：http://www.zackgrossbart.com/hackito/search-engine-python/
一个简易搜索引擎结构，支持对固定网站搜索，但是存在一些不足，只是对按搜索关键词，遍历网站的所有页面，并没有对网站抓取、分词、建索引等。
The ability to search a specific web site for the page you are looking for is a very useful feature. However, searching can be complicated and providing a good search experience can require knowledge of multiple programming languages. This article will demonstrate a simple search engine including a sample application you can run in your own site. This sample application is also a good introduction to the Python programming language.