Peter J C Law added the comment:
Hi,
Sorry for the overkill demo. I've attached a much shorter version, the key
portion of which seems to be that, for the case of UK summer time the timezone,
the tzinfo's `dst()` and `utcoffset()` methods return the same value.
This results in the delta
New submission from Peter J C Law:
There's a difference in behaviour between the ``fromutc`` method on a tzinfo
between Python 2 and Python 3, though only under the specific case of Summer
Time in regions whose usual offset is 0.
From what I can tell, it's the Python 3 one which is wrong
