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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 max_age(self):
 """ Return the MaxAge of the response. :rtype : int :return: the MaxAge option """

        value = defines.OptionRegistry.MAX_AGE.default
        for option in self.options:
            if option.number == defines.OptionRegistry.MAX_AGE.number:
                value = int(option.value)
        return value