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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 _extrapolate_cols(self, data, first=True, last=True):
 """Extrapolate the column of data, to get the first and last together with the data. """


        if first:
            pos = self.col_indices[:2]
            first_column = _linear_extrapolate(pos,
                                               (data[:, 0], data[:, 1]),
                                               self.hcol_indices[0])
        if last:
            pos = self.col_indices[-2:]
            last_column = _linear_extrapolate(pos,
                                              (data[:, -2], data[:, -1]),
                                              self.hcol_indices[-1])

        if first and last:
            return np.hstack((np.expand_dims(first_column, 1),
                              data,
                              np.expand_dims(last_column, 1)))
        elif first:
            return np.hstack((np.expand_dims(first_column, 1),
                              data))
        elif last:
            return np.hstack((data,
                              np.expand_dims(last_column, 1)))
        else:
            return data