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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 entropy(data):
 """ Compute the Shannon entropy, a measure of uncertainty. """


    if len(data) == 0:
        return None

    n = sum(data)

    _op = lambda f: f * math.log(f)
    return - sum(_op(float(i) / n) for i in data)