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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 calculate_current_value(self):
 """ Add all the stock values and assign to the asset classes """

        # must be recursive
        total = Decimal(0)
        for ac in self.classes:
            self.__calculate_current_value(ac)
            total += ac.curr_value
        self.total_amount = total