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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 cleanup(self):
 """ Remove recursive references to allow garbage collector to collect this object. """

        for dict in (self.rule2func, self.rules, self.rule2name):
            for i in list(dict.keys()):
                dict[i] = None
        for i in dir(self):
            setattr(self, i, None)