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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 integral(requestContext, seriesList):
 """ This will show the sum over time, sort of like a continuous addition function. Useful for finding totals or trends in metrics that are collected per minute. Example:: &target=integral(company.sales.perMinute) This would start at zero on the left side of the graph, adding the sales each minute, and show the total sales for the time period selected at the right side, (time now, or the time specified by '&until='). """

    results = []
    for series in seriesList:
        newValues = []
        current = 0.0
        for val in series:
            if val is None:
                newValues.append(None)
            else:
                current += val
                newValues.append(current)
        newName = "integral(%s)" % series.name
        newSeries = TimeSeries(newName, series.start, series.end, series.step,
                               newValues)
        newSeries.pathExpression = newName
        results.append(newSeries)
    return results