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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 hilbert_array(xint):
 """Compute Hilbert indices. Parameters xint: (N, d) int numpy.ndarray Returns ------- h: (N,) int numpy.ndarray Hilbert indices """

    N, d = xint.shape
    h = np.zeros(N, int64)
    for n in range(N):
        h[n] = Hilbert_to_int(xint[n, :])
    return h