This is ongoing and constantly updated for new tips and tricks. While it is lightly organized, the main idea is as a dumping ground. As of 2019-12-06, all examples are developed and tested with Python ...

The deprecation docs are fairly terse in terms of which decorator gets applied where/how. @QuLogic had a really nice write up with examples of how to do deprecation in #26865 and I think it'd be great ...