bpo-33251: Update documentation to reflect change. (GH-6446)

[chrBrd]

Update 3.8 documentation to reflect changes made in #6446 for bpo-33251

https://bugs.python.org/issue33251

[the-knights-who-say-ni]

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[bedevere-bot]

@ambv: Please replace # with GH- in the commit message next time. Thanks!

[ambv]

Thanks!

[ambv]

See #6584.

[chrBrd]

👍

Once again Łukasz, many thanks yourself. I look forward to contributing more in future!