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This patch adds a dropdown to python documentation top toolbar:
https://dl.dropbox.com/u/21052/python/p3_doc_dd.png
This patch version is for python 3.3 & 3.4 docs theme, but I can quickly make patches for 3.2-style and below.
JavaScript that monitors dropdown events is smart enough to:
1) Redirect users to the same documentation section, i.e. if the user is on 'atexit' module doc page for 3.3, and decides to switch to '2.7', he'll see 'atexit' module doc page for 2.7
2) Before making a redirect, is checks that the doc page exists for the selected python version, and if not, then it simply redirects to 'http://docs.python.org/{version}'
3) Users with JS disabled will see a plain-text current version (no drop down)