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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 _check_fill_title_row(self, row_index):
        '''
        Checks the given row to see if it is all titles and fills any blanks cells if that is the
        case.
        '''
        table_row = self.table[row_index]
        # Determine if the whole row is titles
        prior_row = self.table[row_index-1] if row_index > 0 else table_row
        for column_index in range(self.start[1], self.end[1]):
            if is_num_cell(table_row[column_index]) or is_num_cell(prior_row[column_index]):
                return
        # Since we're a title row, stringify the row
        self._stringify_row(row_index)