Bad form for value comparison

[dromer]

All over the code we find examples like:

brave/brave/inputoutputoverlay.py

Line 137 in b9c8e19

if a is not 'state' and hasattr(self, a):

Here value comparison is actually written as object comparison. This is clearly wrong.
Such statements should be written with == and != not with is and is not.

[moschopsuk]

Happy for any PRs to address this 🙂

I've not had much free time recently to go over and address these.