Thanks for the feedback! I can put up a PR to add those changes. 


From: Brett Cannon <>
Sent: Thursday, August 13, 2020 3:34 PM
To: Guido van Rossum <>
Cc: <>; Philippe Prados <>; Maggie Moss <>; Chris Angelico <>
Subject: Re: [Typing-sig] Re: PEP 604 ready for acceptance (Allow writing union types as X | Y)
Not that it matters at this point, but LGTM!

Just two quick things to maybe change in the PEP:

" this operator introduce a dependency" -> "introduces"
" As breaking the backport" reads awkwardly as the other bullet points don't seem to assume reading "Con" before the sentence.

On Thu, Aug 13, 2020 at 3:00 PM Guido van Rossum <> wrote:

On Wed, Aug 12, 2020 at 1:40 PM Guido van Rossum <> wrote:
I'm ready to pronounce PEP 604 as accepted:

With the help of Maggie Moss the PEP has received some updates clarifying the specification; Maggie's implementation is also well under way.

Unless there are objections here within the next 24 hours I will accept the PEP, and the feature will launch in Python 3.10.

Thanks Philippe Prados for bringing this to PEP level and thanks to Maggie for her implementation work.

--Guido van Rossum (

--Guido van Rossum (
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