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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def area(self):
 """The area enclosed by the MOC, in steradians. 3.14 """


        self.normalize()
        area = 0.0

        for (order, cells) in self:
            area += (len(cells) * pi) / (3 * 4 ** order)

        return area