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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_neighbours(self):
 """ Add all the pixels at max order in the neighbourhood of the moc """

        time_delta = 1 << (2*(IntervalSet.HPY_MAX_ORDER - self.max_order))

        intervals_arr = self._interval_set._intervals
        intervals_arr[:, 0] = np.maximum(intervals_arr[:, 0] - time_delta, 0)
        intervals_arr[:, 1] = np.minimum(intervals_arr[:, 1] + time_delta, (1 << 58) - 1)

        self._interval_set = IntervalSet(intervals_arr)