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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 _ProcessHistogram(self, tag, wall_time, step, histo):
 """Processes a proto histogram by adding it to accumulated state."""

    histo = self._ConvertHistogramProtoToTuple(histo)
    histo_ev = HistogramEvent(wall_time, step, histo)
    self.histograms.AddItem(tag, histo_ev)
    self.compressed_histograms.AddItem(tag, histo_ev, self._CompressHistogram)