Return the collapsed object if ``should_collapse()`` is True, otherwise return self.

        :return: A DiscreteStridedIntervalSet object.

def normalize(self):
        """
        Return the collapsed object if ``should_collapse()`` is True, otherwise return self.

        :return: A DiscreteStridedIntervalSet object.
        """
        if self.should_collapse(): return self.collapse()
        elif self.number_of_values == 1: return list(self._si_set)[0]
        else:
            for si in self._si_set:
                self._update_bits(si)
            return self