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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 restore_comments(self, restore_data):
 """Restore comment styles and data """

        for start, end, styles, items in restore_data:
            log.debug("range: %d-%d" % (start, end))
            self.style[start:end] = styles
            for i in range(start, end):
                rawindex, comment = items[i]
                if comment:
                    log.debug("  restoring comment: rawindex=%d, '%s'" % (rawindex, comment))
                    self.rawdata.extra.comments[rawindex] = comment
                else:
                    # no comment in original data, remove any if exists
                    try:
                        del self.rawdata.extra.comments[rawindex]
                        log.debug("  no comment in original data, removed comment in current data at rawindex=%d" % rawindex)
                    except KeyError:
                        log.debug("  no comment in original data or current data at rawindex=%d" % rawindex)
                        pass