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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 A(self):
 """ndarray - a skew-symmetric matrix for integrating the target distribution"""

        wishart = self._wishart_cdf

        base = np.zeros([wishart.size, wishart.size])
        if wishart.n_min % 2:
            # If matrix has odd number of elements, we need to append a
            # row and a col, in order for the pfaffian algorithm to work
            base = self._make_size_even(base)
        return base