While hacking on this I got an Exception. It's better to define
variables also in python.
Signe:-off-by: Adrian Freihofer <adrian.freihofer@siemens.com>
(From OE-Core rev: 1ea225a86cdee4ed932ede509d3351d5aecae497)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>