地址：http://python.org//download//releases//2.7/
一定要加上两个反斜杠，因为http://python.org/download/这个域因Python2.6.4版本被墙了。
- An ordered dictionary type
- New unittest features including test skipping and new assert methods.
- 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
- New syntax for nested with statements
...