Fix PEP8: E225 missing whitespace around operator
Fix PEP8: E226 missing whitespace around arithmetic operator
Fix PEP8: E231 missing whitespace after '[:,]'
Fix PEP8: E241 multiple spaces after ','
Fix PEP8: E251 unexpected spaces around keyword / parameter equals
Fix PEP8: E261 at least two spaces before inline comment
Fix PEP8: W291 trailing whitespace
Lower PEP8 threshold to 150 violations