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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 utilization(prev, curr, counters):
 """ calculate the utilization delta_busy = curr.busy - prev.busy delta_idle = curr.idle - prev.idle utilization = delta_busy / (delta_busy + delta_idle) :param prev: previous resource :param curr: current resource :param counters: list of two, busy ticks and idle ticks :return: value, NaN if invalid. """

    busy_prop, idle_prop = counters

    pb = getattr(prev, busy_prop)
    pi = getattr(prev, idle_prop)

    cb = getattr(curr, busy_prop)
    ci = getattr(curr, idle_prop)

    db = minus(cb, pb)
    di = minus(ci, pi)

    return mul(div(db, add(db, di)), 100)