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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 average_loss(lc):
 """ Given a loss curve array with `poe` and `loss` fields, computes the average loss on a period of time. :note: As the loss curve is supposed to be piecewise linear as it is a result of a linear interpolation, we compute an exact integral by using the trapeizodal rule with the width given by the loss bin width. """

    losses, poes = (lc['loss'], lc['poe']) if lc.dtype.names else lc
    return -pairwise_diff(losses) @ pairwise_mean(poes)