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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 free_dataset(self):
 """Free Booster's Datasets. Returns ------- self : Booster Booster without Datasets. """

        self.__dict__.pop('train_set', None)
        self.__dict__.pop('valid_sets', None)
        self.__num_dataset = 0
        return self