gh-134759: `UnboundLocalError` in `email.message.Message.get_payload`

[skv0zsneg]

Hello!

I worked on #134759 and was able to reproduce the UnboundLocalError by passing bytes payload directly to _payload. I'm not sure can we do it in a "public" way, like throw .set_payload() but if payload some how become bytes (and content-transfer-encoding is equal quoted-printable) it is now not falling :)

I'm also add myself to ACKS list, but not sure is my changes enough for it. If you say I'll remove myself with no questions.

• Issue: gh-134759

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[picnixz]

As a bugfix I think we can keep this but in a follow-up PR I think we should ensure that we are only having a list, str or bytes or handle buffer objects by wrapping them into bytes.

[skv0zsneg]

As a bugfix I think we can keep this but in a follow-up PR I think we should ensure that we are only having a list, str or bytes or handle buffer objects by wrapping them into bytes.

Got it. If nobody mind I can open an issue (or keep in #134759 ?) and take it in work :)

[picnixz]

I'm travelling for now but a separate issue for discussion would be better. It could break backwards compatibility so we should be careful.

[picnixz]

I'm also add myself to ACKS list, but not sure is my changes enough for it. If you say I'll remove myself with no questions.

IMO even contributors fixing a single typo can be added to this file so no worry!

[miss-islington-app[bot]]

Thanks @skv0zsneg for the PR, and @picnixz for merging it 🌮🎉.. I'm working now to backport this PR to: 3.13, 3.14. 🐍🍒⛏🤖

[bedevere-app[bot]]

GH-136579 is a backport of this pull request to the 3.14 branch.

[bedevere-app[bot]]

GH-136580 is a backport of this pull request to the 3.13 branch.