>>177 Python 3.0b3 (r30b3:66303, Sep 8 2008, 14:01:02) [MSC v.1500 32 bit (Intel)] on win32 >>> L = ['one', 'two', 'three', 'four'] >>> L.sort(cmp = lambda a, b: len(a) - len(b)) # 文字数で昇順ソート Traceback (most recent call last): File "<stdin>", line 1, in <module> TypeError: 'cmp' is an invalid keyword argument for this function