C-u d doesn't delete quotes properly when dealing with python-mode

[zadca123]

Hello, again problem with the xah-smart-delete

when pointer is at the end of the line
GROUP_NAME = "group_name"
converts to
ROUP_NAME = "group_name

[xahlee]

hard to fix and won't fix.
the problem is, if the command is based on syntax table, then there's lots problems in arbitrary major modes, such as the builtin python-mode. because they can arbitrary set syntax to chars.
especially prone to happen is quote for string. eg python has so many ways to quote.

a good fix is not relying on syntax table, but one needs to write a nested bracket parser...
maybe i'll do it down the road.