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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 max_allele(self):
 """Return the highest allele index for each variant. Returns ------- n : ndarray, int, shape (n_variants,) Allele index array. Examples -------- array([1, 2, 2], dtype=int8) """


        out = np.empty(self.shape[0], dtype='i1')
        out.fill(-1)
        for i in range(self.shape[1]):
            d = self.values[:, i] > 0
            out[d] = i
        return out