Update python transform catalog

[hjtran]

The python transform catalog page is a bit out of date and includes mentions of transforms that don't exist (PAssert, CombineWithContext, View) and outdated notes about transforms that supposedly haven't been implemented (ApproximateUnique, ApproximateQuantiles).

I've updated the page, removing the unavailable transforms since I'm not sure it's worth mentioning (but I may be missing context) and updated the Approximate* transform entries as well as adding examples for them.

BatchElements also feels like a very useful transform that I've been using personally so I also added it to the catalog.

Example 2 of GroupByKey was also not showing any python

So I tried fixing that as well

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[github-actions]

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[hjtran]

I'm struggling with the linter. Is there a good page for setting it up somewhere?

[damccorm]

I'm struggling with the linter. Is there a good page for setting it up somewhere?

Could you take a look at https://cwiki.apache.org/confluence/display/BEAM/Python+Tips#PythonTips-LintandFormattingChecks

[damccorm]

Thanks for doing this! I had some questions/thoughts, but think this is great overall!

Also, btw in case you haven't noticed this, beam generates a staged version of the website on PRs as part of an action - see the link here for example https://github.com/apache/beam/actions/runs/8532860668?pr=30788 - you may have seen it already, but wanted to call it out just in case

[damccorm]

I think these won't render until the next playground release. So it may make sense to split this into 2 PRs, one for now and one for once the playground piece is released after 2.56

[hjtran]

Ah, so the website can get upgraded within a release but playground gets redeployed with releases.

It's all a bit tangled and I'm not sure I have the time to split it apart. Would it be alright to just keep the PR as is and merge whenever it makes sense? (assuming there is such a moment)

[damccorm]

There's not a great single time to merge since we'd want the playground on the release branch, so we'd want to merge the playground fixes, wait a week or so for the release, then merge the website changes.

With that said, if you definitely don't have time we can merge right before the release branch is cut (I'm running the release so should be easy for me to pick up) and the website will just be broken for a bit in these code samples. It isn't ideal, but would probably still be better than not doing this at all.

Up to you on how to proceed here, I'll add this as a release blocker so I remember to merge though

[damccorm]

Outside of the linting failure the changes look good to me, so just let me know how you'd prefer to proceed

[github-actions]

Reminder, please take a look at this pr: @damccorm @damccorm

[damccorm]

@hjtran I added a few suggestions that I think will clean up the linting failures based on the logs. I'm going to batch commit them to see if it helps since I'd love to get this in before the release branch cut tomorrow

[hjtran]

SGTM, thanks @damccorm ! Sorry I didn't have time to take another look at this last week.

[damccorm]

No problem - looks like it did fix the lint checks, so I'll merge once the coverage check finishes (assuming nothing broke unexpectedly)

[damccorm]

Only test failure is testPy38tft-113 which is known to be flaky. Merging