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Author vstinner
Recipients Anthony Sottile, abartlet, miss-islington, pitrou, serhiy.storchaka, vstinner
Date 2020-03-04.13:08:41
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Le mer. 4 mars 2020 à 03:01, Andrew Bartlett <> a écrit :
> (...) but that a valid build script that operates correctly on Python 3.8 will no longer, without warning to us, (...)

Displaying warnings by default or not is an old debate.

I added the "Python Development Mode" (-X dev) to help the situation:

I just added a very explicit "You should check for DeprecationWarning in your code" section in What's New In Python 3.9:

Moreover, DeprecationWarning are now (Python 3.7) displayed *by default* in the __main__ module:
Date User Action Args
2020-03-04 13:08:41vstinnersetrecipients: + vstinner, pitrou, serhiy.storchaka, Anthony Sottile, miss-islington, abartlet
2020-03-04 13:08:41vstinnersetmessageid: <>
2020-03-04 13:08:41vstinnerlinkissue37330 messages
2020-03-04 13:08:41vstinnercreate