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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 natural_breaks(values, k=5):
 """ natural breaks helper function Jenks natural breaks is kmeans in one dimension """

    values = np.array(values)
    uv = np.unique(values)
    uvk = len(uv)
    if uvk < k:
        Warn('Warning: Not enough unique values in array to form k classes',
             UserWarning)
        Warn('Warning: setting k to %d' % uvk, UserWarning)
        k = uvk
    kres = _kmeans(values, k)
    sids = kres[-1]  # centroids
    fit = kres[-2]
    class_ids = kres[0]
    cuts = kres[1]
    return (sids, class_ids, fit, cuts)