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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 _add_delta_tdi(self, other):
 """ Add a delta of a TimedeltaIndex return the i8 result view """

        if len(self) != len(other):
            raise ValueError("cannot add indices of unequal length")

        if isinstance(other, np.ndarray):
            # ndarray[timedelta64]; wrap in TimedeltaIndex for op
            from pandas import TimedeltaIndex
            other = TimedeltaIndex(other)

        self_i8 = self.asi8
        other_i8 = other.asi8
        new_values = checked_add_with_arr(self_i8, other_i8,
                                          arr_mask=self._isnan,
                                          b_mask=other._isnan)
        if self._hasnans or other._hasnans:
            mask = (self._isnan) | (other._isnan)
            new_values[mask] = iNaT
        return new_values.view('i8')