clean etherlab: pep8, W602 deprecated form of raising exception

clean etherlab: pep8, W601 .has_key() is deprecated, use 'in'

clean etherlab: pep8, E731 do not assign a lambda expression, use a def

clean etherlab: pep8, E203 whitespace before ','

clean etherlab: pep8, E712 comparison to True should be 'if cond is True:' or 'if cond:'

clean etherlab: pep8, E222 multiple spaces after operator

clean etherlab: pep8, E741 ambiguous variable name 'l'

cleanup etherlab: pep8, E306 expected 1 blank line before a nested definition, found X

cleanup etherlab: pep8, E305 expected 2 blank lines after class or function definition, found X

cleanup etherlab: pep8, E201 whitespace after '('

cleanup etherlab: pep8, E202 whitespace before ')'

cleanup etherlab: pep8, E227 missing whitespace around bitwise or shift operator

cleanup etherlab: pep8, E251 unexpected spaces around keyword / parameter equals

cleanup etherlab: pep8, E225 missing whitespace around operator

cleanup etherlab: pep8, E303 too many blank lines (2)

cleanup etherlab: pep8, E231 missing whitespace after ','