clean-up: fix PEP8 E115 expected an indented block (comment)

clean-up: fix PEP8 E721 do not compare types, use 'isinstance()'

clean-up: fix PEP8 E131 continuation line unaligned for hanging indent

clean-up: fix PEP8 E122 continuation line missing indentation or outdented

clean-up: fix PEP8 E713 test for membership should be 'not in'

clean-up: fix PEP8 E272 multiple spaces before keyword

clean-up: fix PEP8 E124 closing bracket does not match visual indentation

clean-up: fix PEP8 W191 indentation contains tabs

clean-up: fix PEP8 E211 whitespace before '[' or '('

clean-up: fix PEP8 E114 indentation is not a multiple of four (comment)

clean-up: fix PEP8 E125 continuation line with same indent as next logical line

clean-up: fix PEP8 E128 continuation line under-indented for visual indent