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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 trees(return_X_y=True):
 """cherry trees dataset Parameters return_X_y : bool, if True, returns a model-ready tuple of data (X, y) otherwise, returns a Pandas DataFrame Returns ------- model-ready tuple of data (X, y) OR Pandas DataFrame Notes ----- X contains the girth and the height of each tree. y contains the volume. Source: https://vincentarelbundock.github.io/Rdatasets/doc/datasets/trees.html """

    # y is real.
    # recommend InvGaussGAM, or GAM(distribution='gamma', link='log')
    trees = pd.read_csv(PATH + '/trees.csv', index_col=0)
    if return_X_y:
        y = trees.Volume.values
        X = trees[['Girth', 'Height']].values
        return _clean_X_y(X, y)
    return trees