def uncorrected_stdev(iterable):
    if not iterable:
        return None
    if len(iterable) == 1:
        return 0
    iter_mean = mean(iterable)
    deltas = [(x - iter_mean) ** 2 for x in iterable]
    variance = float(sum(deltas)) / len(iterable)
    return math.sqrt(variance)
This implementation of standard deviation uses an uncorrected variance
dataset/ETHPy150Open swiftstack/ssbench/ssbench/util.py/uncorrected_stdev