New rule for tzinfo subclasses handling both standard and daylight time:

When daylight time ends, an hour repeats on the local clock (for example,
in US Eastern, the clock jumps from 1:59 back to 1:00 again).  Times in
the repeated hour are ambiguous.  A tzinfo subclass that wants to play
with astimezone() needs to treat times in the repeated hour as being
standard time.  astimezone() previously required that such times be
treated as daylight time.  There seems no killer argument either way,
but Guido wants the standard-time version, and it does seem easier the
new way to code both American (local-time based) and European (UTC-based)
switch rules, and the astimezone() implementation is simpler.

1 files changed, 1 insertions, 1 deletions

diff --git a/Doc/lib/tzinfo-examples.py b/Doc/lib/tzinfo-examples.py
index cea0309..b488dd0 100644
--- a/Doc/lib/tzinfo-examples.py
+++ b/Doc/lib/tzinfo-examples.py
@@ -91,7 +91,7 @@ def first_sunday_on_or_after(dt):
 DSTSTART = datetime(1, 4, 1, 2)
 # and ends at 2am (DST time; 1am standard time) on the last Sunday of Oct.
 # which is the first Sunday on or after Oct 25.
-DSTEND = datetime(1, 10, 25, 2)
+DSTEND = datetime(1, 10, 25, 1)
 
 class USTimeZone(tzinfo):