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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 _longest_val_in_column(self, col):
 """ get size of longest value in specific column :param col: str, column name :return int """

        try:
            # +2 is for implicit separator
            return max([len(x[col]) for x in self.table if x[col]]) + 2
        except KeyError:
            logger.error("there is no column %r", col)
            raise