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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 _set_value(self, slot_record):
 """Sets the value of this slot based on its corresponding _SlotRecord. Does nothing if the slot has not yet been filled. Args: slot_record: The _SlotRecord containing this Slot's value. """

    if slot_record.status == _SlotRecord.FILLED:
      self.filled = True
      self._filler_pipeline_key = _SlotRecord.filler.get_value_for_datastore(
          slot_record)
      self._fill_datetime = slot_record.fill_time
      self._value = slot_record.value