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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 _second_column(self):
 """Right-low 2x2 matrix Assume elements in first row and column are all zero except for A[0,0]. """


        if self._A[1, 1] == 0 and self._A[2, 1] != 0:
            self._swap_rows(1, 2)

        if self._A[2, 1] != 0:
            self._zero_second_column()