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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 add_col(self, label):
 """ Update table dataframe, and append a new column Parameters label : str Returns --------- last_col: int index column number of added col """

        self.table.dataframe[label] = ''
        self.AppendCols(1, updateLabels=False)
        last_col = self.table.GetNumberCols() - 1
        self.SetColLabelValue(last_col, label)
        self.col_labels.append(label)
        self.size_grid()
        return last_col