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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 offsetToZero(requestContext, seriesList):
 """ Offsets a metric or wildcard seriesList by subtracting the minimum value in the series from each datapoint. Useful to compare different series where the values in each series may be higher or lower on average but you're only interested in the relative difference. An example use case is for comparing different round trip time results. When measuring RTT (like pinging a server), different devices may come back with consistently different results due to network latency which will be different depending on how many network hops between the probe and the device. To compare different devices in the same graph, the network latency to each has to be factored out of the results. This is a shortcut that takes the fastest response (lowest number in the series) and sets that to zero and then offsets all of the other datapoints in that series by that amount. This makes the assumption that the lowest response is the fastest the device can respond, of course the more datapoints that are in the series the more accurate this assumption is. Example:: &target=offsetToZero(Server.instance01.responseTime) &target=offsetToZero(Server.instance*.responseTime) """

    for series in seriesList:
        series.name = "offsetToZero(%s)" % (series.name)
        minimum = safeMin(series)
        for i, value in enumerate(series):
            if value is not None:
                series[i] = value - minimum
    return seriesList