Pylint: False positive undefined-variable with nested lambdas in pylint for python 2

[yaccz]

The issue has been reported at #760 and fixed by #2274. However, the fix is merged only into pylint 2.x which supports only python >= 3.4 leaving us with the bug unresolved in the pylint 1.x series for python 2.

[yaccz]

Cherry picking db01112f7e4beadf7cd99c5f9237d580309f0494 on top 1.9 seems fairly straightforward and while tox -e py27 on the cherry picking gives me some errors, they dont seem be to be regressions against 1.9 HEAD.

[PCManticore]

Thanks for reporting an issue @yaccz Feel free to submit a PR against 1.9, I'll do a release with it if it's green.

[yaccz]

I've submitted the backport. It aint green but also not regressing as far as I can tell.

I'm also not too sure about the ChangeLog change as I am not familiar with your change logging setup.

[yaccz]

bump?

[PCManticore]

Just released 1.9.4. Thanks!