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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 ci(arr, conf=0.95):
 """ Column-wise confidence interval. Parameters arr : array-like conf : float Confidence interval Returns ------- m : array column-wise mean lower : array lower column-wise confidence bound upper : array upper column-wise confidence bound """

    m = arr.mean(axis=0)
    n = len(arr)
    se = arr.std(axis=0) / np.sqrt(n)
    h = se * stats.t._ppf((1 + conf) / 2., n - 1)
    return m, m - h, m + h