http://subtech.g.hatena.ne.jp/otsune/20060621/pythonreservedwords
>>> __import__('keyword').kwlist ['and', 'assert', 'break', 'class', 'continue', 'def', 'del', 'elif', 'else', 'except', 'exec', ' finally', 'for', 'from', 'global', 'if', 'import', 'in', 'is', 'lambda', 'not', 'or', 'pass', 'print', 'raise', 'return', 'try', 'while', 'yield']
