def get_all_longest_col_lengths(self):
        response = {}
        for col in self.col_list:
            response[col] = self._longest_val_in_column(col)
        return response
iterate over all columns and get their longest values
dataset/ETHPy150Open projectatomic/osbs-client/osbs/cli/render.py/TablePrinter.get_all_longest_col_lengths