gh-99908 Update class documentation to use a modernized example

[JosephSBoyle]

Small update to the docs to improve on an outmoded example from 15 years ago.
The aim of this change is to give readers of the docs a more idiomatic example.

• Issue: classes odds and ends could mention dataclasses #99908

[cpython-cla-bot]

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• joe.boyle@blackcowtech.uk

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[sobolevn]

Hi, @JosephSBoyle! Could you please sign a CLA? We cannot accept your PR without it :(

[JosephSBoyle]

Hi @sobolevn. I have accepted the CLA. Can you re-run the check please? (I had to change my email address in the commit to my GH one).

[sobolevn]

@JosephSBoyle are you sure that your git email is the same as your CLA email: joe.boyle@blackcowtech.uk?
Looks like CLA status is not updated :(
Usually it happens in <1 hour.

[JosephSBoyle]

Hi @sobolevn, thanks for the reminder- I had to rebase and edit my email in the commit log to have the same email as my CLA. Should be fine now:)

[AlexWaygood]

Hi @sobolevn, thanks for the reminder- I had to rebase and edit my email in the commit log to have the same email as my CLA. Should be fine now:)

Looks like the CLA bot is still being grumpy — it might be easier to just close the PR and recreate it :)