def _firstOrLastValue(self, field, currentIndex, otherIndex):
        currentValue = self._origList[currentIndex] # Raises IndexError.
        try:
            otherValue = self._origList[otherIndex]
        except IndexError:
            return True
        if field:
            currentValue = lookup_func(currentValue, field)
            otherValue = lookup_func(otherValue, field)
        return currentValue is not otherValue
dataset/ETHPy150Open skyostil/tracy/src/generator/Cheetah/Tools/MondoReport.py/RecordStats._firstOrLastValue/operator `!=` -> `is not`