saltstack/salt — pull request #484 by lzyeval (2012-01-11 05:23:09+00:00)
Title: PEP8 type clean-up

Fixes issue #480

The None, True, and False values are singletons.

All variable comparisons to singletons should use 'is' or 'is not'.
All variable evaluations to boolean should use 'if' or 'if not'.
All Object type comparisons should use isinstance()
instead of comparing types directly.