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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_column(self, column_index):
        '''
        Same as _check_fill_title_row but for columns.
        '''
        # Determine if the whole column is titles
        table_column = TableTranspose(self.table)[column_index]
        prior_column = TableTranspose(self.table)[column_index-1] if column_index > 0 else table_column
        for row_index in range(self.start[0], self.end[0]):
            if is_num_cell(table_column[row_index]) or is_num_cell(prior_column[row_index]):
                return
        # Since we're a title row, stringify the column
        self._stringify_column(column_index)