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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 io_size_kb(prev, curr, counters):
 """ calculate the io size based on bandwidth and throughput formula: average_io_size = bandwidth / throughput :param prev: prev resource, not used :param curr: current resource :param counters: two stats, bandwidth in MB and throughput count :return: value, NaN if invalid """

    bw_stats, io_stats = counters
    size_mb = div(getattr(curr, bw_stats), getattr(curr, io_stats))
    return mul(size_mb, 1024)