I'm struggling with learning vim regexps (I don't know any other regexp very well either), so the main problem is to define regexp that would match
keyword in this example.
So it should match a word if it's inside parens and have equal sign after it.
The next problem is how to define syntax files in vim. I would appreciate help with that, but It shouldn't be that hard to learn, so I can do that on my own probably.
EDIT based on the answer I've maid my own syntax script for python. Feel free to try it. enter link description here