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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 import_libsvm_sparse(filename):
 """Imports dataset file in libsvm sparse format"""

    from sklearn.datasets import load_svmlight_file
    X, y = load_svmlight_file(filename)
    return Dataset(X.toarray().tolist(), y.tolist())