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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 load_jester():
 """Ratings from the Jester Online Joke Recommender System. This dataset consists of over 1.7 million instances of (user_id, item_id, rating) triples, which is split 50-50 into train and test data. source: "University of California Berkeley, CA" sourceURI: "http://eigentaste.berkeley.edu/dataset/" """


    dataset_path = _load('jester')

    X = _load_csv(dataset_path, 'data')
    y = X.pop('rating').values

    return Dataset(load_jester.__doc__, X, y, r2_score)