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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 calc_deviation(values, average):
 """ Calculate the standard deviation of a list of values @param values: list(float) @param average: @return: """

    size = len(values)
    if size < 2:
        return 0
    calc_sum = 0.0

    for number in range(0, size):
        calc_sum += math.sqrt((values[number] - average) ** 2)
    return math.sqrt((1.0 / (size - 1)) * (calc_sum / size))