This release improves our support for datetimes and times around DST
transitions.
"times()" and "datetimes()" are now sometimes generated with "fold=1",
indicating that they represent the second occurrence of a given wall-
time when clocks are set backwards. This may be set even when there is
no transition, in which case the "fold" value should be ignored.
For consistency, timezones provided by the pytz package can now
generate imaginary times (such as the hour skipped over when clocks
'spring forward' to daylight saving time, or during some historical
timezone transitions). All other timezones have always supported
generation of imaginary times.
If you prefer the previous behaviour, "datetimes()" now takes an
argument "allow_imaginary" which defaults to "True" but can be set to
"False" for any timezones strategy.
The canonical version of these notes (with links) is on readthedocs.