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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 design(npos):
 """ make a design matrix for an anisotropy experiment """

    if npos == 15:
        #
        # rotatable design of Jelinek for kappabridge (see Tauxe, 1998)
        #
        A = np.array([[.5, .5, 0, -1., 0, 0], [.5, .5, 0, 1., 0, 0], [1, .0, 0, 0, 0, 0], [.5, .5, 0, -1., 0, 0], [.5, .5, 0, 1., 0, 0], [0, .5, .5, 0, -1., 0], [0, .5, .5, 0, 1., 0], [0, 1., 0, 0, 0, 0],
                      [0, .5, .5, 0, -1., 0], [0, .5, .5, 0, 1., 0], [.5, 0, .5, 0, 0, -1.], [.5, 0, .5, 0, 0, 1.], [0, 0, 1., 0, 0, 0], [.5, 0, .5, 0, 0, -1.], [.5, 0, .5, 0, 0, 1.]])  # design matrix for 15 measurment positions
    elif npos == 6:
        A = np.array([[1., 0, 0, 0, 0, 0], [0, 1., 0, 0, 0, 0], [0, 0, 1., 0, 0, 0], [.5, .5, 0, 1., 0, 0], [
                     0, .5, .5, 0, 1., 0], [.5, 0, .5, 0, 0, 1.]])  # design matrix for 6 measurment positions

    else:
        print("measurement protocol not supported yet ")
        return
    B = np.dot(np.transpose(A), A)
    B = linalg.inv(B)
    B = np.dot(B, np.transpose(A))
    return A, B