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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 rangeOfSeries(requestContext, *seriesLists):
 """ Takes a wildcard seriesList. Distills down a set of inputs into the range of the series Example:: &target=rangeOfSeries(Server*.connections.total) """

    if not seriesLists or not any(seriesLists):
        return []
    seriesList, start, end, step = normalize(seriesLists)
    name = "rangeOfSeries(%s)" % formatPathExpressions(seriesList)
    values = (safeSubtract(max(row),
                           min(row)) for row in zip_longest(*seriesList))
    series = TimeSeries(name, start, end, step, values)
    series.pathExpression = name
    return [series]