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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 freeze(self):
 """ Freezes this Config object, disallowing modification or addition of any parameters. """

        if getattr(self, '_frozen'):
            return
        object.__setattr__(self, "_frozen", True)
        for k, v in self.__dict__.items():
            if isinstance(v, Config) and k != "self":
                v.freeze()