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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 _generate_permutation(self, npoints):
 """ Create shuffle and deshuffle vectors """

        i = np.arange(0, npoints)
        # permutation
        p = np.random.permutation(npoints)
        ip = np.empty_like(p)
        # inverse permutation
        ip[p[i]] = i
        return p, ip