1 October 2008 (posted 6 December 2009)
This article explains the new features in Python 2.6, released on October 1 2008. The release schedule is described in PEP 361.
The major theme of Python 2.6 is preparing the migration path to Python 3.0, a
major redesign of the language. Whenever possible, Python 2.6 incorporates new
features and syntax from 3.0 while remaining compatible with existing code by
not removing older features or syntax. When it’s not possible to do that,
Python 2.6 tries to do what it can, adding compatibility functions in a
future_builtins module and a -3 switch to warn about usages that will
become unsupported in 3.0.
Some significant new packages have been added to the standard library, such as
the multiprocessing and json modules, but there aren’t many new features
that aren’t related to Python 3.0 in some way.
Python 2.6 also sees a number of improvements and bugfixes throughout the source. A search through the change logs finds there were 259 patches applied and 612 bugs fixed between Python 2.5 and 2.6. Both figures are likely to be underestimates.
This article doesn’t attempt to provide a complete specification of the new features, but instead provides a convenient overview. For full details, you should refer to the documentation for Python 2.6. If you want to understand the rationale for the design and implementation, refer to the PEP for a particular new feature. Whenever possible, “What’s New in Python” links to the bug/patch item for each change.