On the second reading, I have a few issues with the patch.

1. Please run makepatcheck.  There are whitespace issues in datetime.rst.
2. In docstrings, you remove the information about the sign.  I would not mind leaving docstrings the way they are.  Otherwise, please add a short sentence explaining the sign of utcoffset and dst.
3. "This represents the offset in minutes that must be added to the local time zone to follow DST rules."   This unclear.  DST offset is added to the "standard time", not "local time zone".  (I am not sure if "standard time" is defined in the manual, though.)  Also, "in minutes" is not necessary - timedelta carries the units. You can add that only offsets that are multiples of a minute are supported.