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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 get_or_create_time_series(self, label_values):
 """Get a mutable measurement for the given set of label values. :type label_values: list(:class:`LabelValue`) :param label_values: The measurement's label values. :rtype: :class:`GaugePointLong`, :class:`GaugePointDouble` :class:`opencensus.metrics.export.cumulative.CumulativePointLong`, or :class:`opencensus.metrics.export.cumulative.CumulativePointDouble` :return: A mutable point that represents the last value of the measurement. """

        if label_values is None:
            raise ValueError
        if any(lv is None for lv in label_values):
            raise ValueError
        if len(label_values) != self._len_label_keys:
            raise ValueError
        return self._get_or_create_time_series(label_values)