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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 update_col(self, column_name, series):
 """ Add or replace a column in the underlying DataFrame. Parameters column_name : str Column to add or replace. series : pandas.Series or sequence Column data. """

        logger.debug('updating column {!r} in table {!r}'.format(
            column_name, self.name))
        self.local[column_name] = series