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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 get(self, col_str):
        '''
        get one data column with the data

        Parameters
        ----------
        col_str : string
            One of the column strings in self.cols.

        '''
        data_column=zeros(self.ilines)
        for i in range(self.ilines):
            data_column[i]=self.data[i][self.col_num[col_str]]
        return data_column