Pick another example for the document Argument Clinic How-To

Hi, fellows of the Python community. I wish I could find the right way. Recently, I found the example in the article Argument Clinic How-To cannot cover all cases for its usage. In the article, the author used the method _pickle.Pickler.dump to illustrate how to use AC and the method is so simple that many cases are skipped (e.g. step 5, 9, 13). Many readers will be confused since the lack of examples. I found a perfect method _asyncio.Future.add_done_callback can cover all cases. I rewrote the article and here is my PR: gh-106799: Pick another example method for Argument Clinic How-To by littlebutt · Pull Request #106800 · python/cpython · GitHub . Is it necessary? If the change is unnecessary I will close it. Thank you all.