Python 2.7.4 RC 发布了，下载地址：http://www.python.org/download/releases/2.7.4/
这是一个维护版本，同时也包含 3.1 版本中的一些新特性：
An ordered dictionary type
New unittest features including test skipping, new assert methods, and test discovery
A much faster io module
Automatic numbering of fields in the str.format() method
Float repr improvements backported from 3.x
Tile support for Tkinter
A backport of the memoryview object from 3.x
Set literals
Set and dictionary comprehensions
Dictionary views
New syntax for nested with statements
The sysconfig module
来自:开源中国社区
