On Fri, Aug 28, 2015 at 7:51 PM, Guido van Rossum <guido@python.org> wrote:

On Fri, Aug 28, 2015 at 6:53 PM, Guido van Rossum <guido@python.org>

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wrote:

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I'm not entirely sure why we didn't add this to the stdlib ages ago.

But (as my base class shows) implementing the required API using only the tm_isdst flag and the timezone-related attributes of the time module (tzname, timezone, altzone) a satisfactory implementation can be obtained, and that API has been stable since the beginning of time.

To be fair, we did ship something very similar, but it was only accessible to users who read the library manual: < https://hg.python.org/cpython/file/v3.5.0rc2/Doc/includes/tzinfo-examples.py...>. :-)