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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 std_dev(xs):
 """ Returns the standard deviation of the given iterable of numbers. From http://rosettacode.org/wiki/Standard_deviation#Python An empty list, or a list with non-numeric elements will raise a TypeError. 2.0 2.0 8.049844718999243 True 0.0 Traceback (most recent call last):
 ValueError: Input can't have non-numeric elements Traceback (most recent call last):
 ValueError: Input can't be empty """

    m = mean(xs)  # this checks our pre-conditions, too
    return sqrt(sum((x - m) ** 2 for x in xs) / float(len(xs)))