相关疑难解决方法(0)

以下代码有效:

class Foo(tuple):

    def __init__(self, b):
        super(Foo, self).__init__(tuple(b))

if __name__ == '__main__':
    print Foo([3, 4])

$ python play.py 

结果:

play.py:4: DeprecationWarning: object.__init__() takes no parameters
  super(Foo, self).__init__(tuple(b))
(3, 4)

但不是以下内容:

class Foo(tuple):

    def __init__(self, a, b):
        super(Foo, self).__init__(tuple(b))

if __name__ == '__main__':
    print Foo(None, [3, 4])

$ python play.py 

结果:

Traceback (most recent call last):
  File "play.py", line 7, in <module>
    print Foo(None, [3, 4])
TypeError: tuple() takes at most 1 argument (2 given)

为什么？