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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 regular(self):
 """`True` if this index is linearly increasing """

        try:
            return self.info.meta['regular']
        except (TypeError, KeyError):
            if self.info.meta is None:
                self.info.meta = {}
            self.info.meta['regular'] = self.is_regular()
            return self.info.meta['regular']