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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 normalize(X):
 """ equivalent to scipy.preprocessing.normalize on sparse matrices , but lets avoid another depedency just for a small utility function """

    X = coo_matrix(X)
    X.data = X.data / sqrt(bincount(X.row, X.data ** 2))[X.row]
    return X