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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 get_normalized_grid(self):
 """ Analyzes subcell structure """

        log = logging.getLogger(__name__)
        # Resolve multirow mentions, TODO: validate against all PDFs
        #  subcol_count = 0
        mega_rows = []
        for row_id, row in enumerate(self._grid):
            # maps yc_grid -> [mentions]
            subrow_across_cell = defaultdict(list)
            for col_id, cell in enumerate(row):
                # Keep cell text in reading order
                cell.texts.sort(key=cmp_to_key(reading_order))
                log.debug("=" * 50)
                for m in cell.texts:
                    subrow_across_cell[m.yc_grid].append(m)
                    #  prev = m

            log.debug(pformat(dict(subrow_across_cell)))

            mega_rows.append(subrow_across_cell)

        # Multiline paragraph check
        # Subrow/Subcolumn

        return mega_rows