def _fill_row_holes(self):
        '''
        Fill any remaining row title cells that are empty. This must be done after the other passes
        to avoid preemptively filling in empty cells reserved for other operations.
        '''
        for row_index in range(self.start[0], self.max_title_row):
            table_row = self.table[row_index]
            row_start = table_row[self.start[1]]
            if is_text_cell(row_start):
                self._check_fill_title_row(row_index)
Fill any remaining row title cells that are empty. This must be done after the other passes
        to avoid preemptively filling in empty cells reserved for other operations.