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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 round_60(value):
 """ round the number to the multiple of 60 Say a random value is represented by: 60 * n + r n is an integer and r is an integer between 0 and 60. if r < 30, the result is 60 * n. otherwise, the result is 60 * (n + 1) The use of this function is that the counter refreshment on VNX is always 1 minute. So the delta time between samples of counters must be the multiple of 60. :param value: the value to be rounded. :return: result """

    t = 60
    if value is not None:
        r = value % t
        if r > t / 2:
            ret = value + (t - r)
        else:
            ret = value - r
    else:
        ret = NaN
    return ret