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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 d2Sbus_dV2(Ybus, V, lam):
 """ Computes 2nd derivatives of power injection w.r.t. voltage. """

    n = len(V)
    Ibus = Ybus * V
    diaglam = spdiag(lam)
    diagV = spdiag(V)

    A = spmatrix(mul(lam, V), range(n), range(n))
    B = Ybus * diagV
    C = A * conj(B)
    D = Ybus.H * diagV
    E = conj(diagV) * (D * diaglam - spmatrix(D*lam, range(n), range(n)))
    F = C - A * spmatrix(conj(Ibus), range(n), range(n))
    G = spmatrix(div(matrix(1.0, (n, 1)), abs(V)), range(n), range(n))

    Gaa = E + F
    Gva = 1j * G * (E - F)
    Gav = Gva.T
    Gvv = G * (C + C.T) * G

    return Gaa, Gav, Gva, Gvv