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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 percentileOfSeries(requestContext, seriesList, n, interpolate=False):
 """ percentileOfSeries returns a single series which is composed of the n-percentile values taken across a wildcard series at each point. Unless `interpolate` is set to True, percentile values are actual values contained in one of the supplied series. """

    if n <= 0:
        raise ValueError(
            'The requested percent is required to be greater than 0')

    if not seriesList:
        return []
    name = 'percentileOfSeries(%s,%g)' % (seriesList[0].pathExpression, n)
    start, end, step = normalize([seriesList])[1:]
    values = [_getPercentile(row, n, interpolate)
              for row in zip_longest(*seriesList)]
    resultSeries = TimeSeries(name, start, end, step, values)
    resultSeries.pathExpression = name
    return [resultSeries]