python - 带有 required_arg、*args、**kwargs 的类定义

Question

除了 *args、**kwargs 之外，我还想在来自另一个类的类中使用一个 required_arg。但目前我没有成功!这段代码:

class PageNumCanvas(canvas.Canvas):
    "For  add \"page number of total\" in each footer."

    def __init__(self, page1, *args, **kwargs):
        "Constructor."
        self.page1 = page1 - 1
        canvas.Canvas.__init__(self, *args, **kwargs)
        self.pages = []

当我这样做时出现错误消息:canvasmaker = PageNumCanvas(1):

canvas.Canvas.__init__(self, *args, **kwargs)
    TypeError: __init__() takes at least 2 arguments (1 given)

如何使用 page1 参数调用 PageNumCanvas 类？

更新#1:

如果我不在类的 init 中使用参数，我就没有问题。例如:

>>> from reportlab.pdfgen import canvas
>>> class PageNumCanvas(canvas.Canvas):
...     "For  add \"page number of total\" in each footer."
...     def __init__(self, *args, **kwargs):
...             canvas.Canvas.__init__(self, *args, **kwargs)
...             self.pages = []
... 
>>> canvasmaker = PageNumCanvas(1)
>>> canvasmaker
<__main__.PageNumCanvas instance at 0x7f618195df38>
>>> 

更新#2:感谢goncalopp提供的方法，正确的代码是:

class PageNumCanvas(canvas.Canvas):
...     "For  add \"page number of total\" in each footer."
...     def __init__(self, page1, *args, **kwargs):
...             "Constructor."
...             canvas.Canvas.__init__(self, page1, *args, **kwargs)
...             self.page1 = page1 - 1
...             self.pages = []
...             print self.page1
... 
>>> canvasmaker = PageNumCanvas(12)
11
>>> 

Answer 1

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canvas.Canvas.__init__(self, page1, *args, **kwargs)