md5(Message-Digest Algorithm 5) 模块用于计算信息密文（信息摘要），得出一个128位的密文。sha模块跟md5相似，但生成的是160位的签名。使用方法是相同的。
Mezzanine has come a long way over the last few years, now powering hundreds of rich, content-driven sites. For the most part these sites follow a similar pattern, one which Mezzanine is heavily geared towards: B2C sites comprised of heterogeneous, hierarchical content. In this regard Mezzanine has been a huge success, however in its entirety it’s capable of quite a lot more. Out of the box it provides a range of useful utilities, that aren’t particularly geared towards a typical corporate site, but instead are aimed at a more social style of web application. These include things such as public user accounts with configurable profiles, threaded comment discussions, ratings, and much more - features that form the foundation of many of today’s most popular social web apps. This presents Mezzanine as a great foundation for building all types of social web applications, not just corporate, content-driven sites.
A project of mine contains a number of third-party apps that are development
related and potentially not available on every machine the project will run
on. My general approach to dealing with these was to try and import the app in
settings module and if successful, add it to the
setting. However as the number of these apps grew it became a wart within the
settings module so I put together this snippet for managing them.