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* I did not to go with a single page for all this content b/c both java and python have enough unique content that they deserve their own separate sections (ie, just tabs on the code isn't enough), and the "click to the next page" model currently implemented allows the user to pick java vs python, but then after reading those pages, the next page for both points at the same place - the users mostly follow the same path, but for java vs python specific content, they will diverge then converge again.
* I moved the "list of built-in I/O" content over to it's own separate page since it'd be nice to have more content there - e.g. capabilities matrix, and it felt special enough to pull out of the programming guide.
* We decided not to put all of this content in the contribute section of the site since the expectation is we don't think all users will contribute their IO transforms, so we want most of the docs to just be about writing an IO transforms, and they lay out the expectations in the contribute part of the IO section.

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