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Complete this python program:
def kkt_ldl(G, dims, A, mnl=0):
assistant
#Here is the Python program you requested.

    """Solution of KKT equations by a dense LDL factorization of the
    3 x 3 system.
    Returns a function that (1) computes the LDL factorization of
    [ H           A\   GG\*W^{-1} ]
    [ A           0    0          ],
    [ W^{-T}*GG   0   -I          ]
    given H, Df, W, where GG = [Df; G], and (2) returns a function for
    solving
    [ H     A\   GG\   ]   [ ux ]   [ bx ]
    [ A     0    0     ] * [ uy ] = [ by ].
    [ GG    0   -W\*W  ]   [ uz ]   [ bz ]
    H is n x n,  A is p x n, Df is mnl x n, G is N x n where
    N = dims[\l\] + sum(dims[\q\]) + sum( k**2 for k in dims[\s\] ).
    """
    from cvxopt import blas, lapack
    from cvxopt.base import matrix
    from cvxopt.misc import scale, pack, unpack
    (p, n) = A.size
    ldK = (((((n + p) + mnl) + dims['l']) + sum(dims['q'])) + sum([int(((k * (k + 1)) / 2)) for k in dims['s']]))
    K = matrix(0.0, (ldK, ldK))
    ipiv = matrix(0, (ldK, 1))
    u = matrix(0.0, (ldK, 1))
    g = matrix(0.0, ((mnl + G.size[0]), 1))
    def factor(W, H=None, Df=None):
        blas.scal(0.0, K)
        if (H is not None):
            K[:n, :n] = H
        K[n:(n + p), :n] = A
        for k in range(n):
            if mnl:
                g[:mnl] = Df[:, k]
            g[mnl:] = G[:, k]
            scale(g, W, trans='T', inverse='I')
            pack(g, K, dims, mnl, offsety=(((k * ldK) + n) + p))
        K[((ldK + 1) * (p + n))::(ldK + 1)] = (-1.0)
        K[0:((ldK + 1) * n):(ldK + 1)] += REG_EPS
        K[((ldK + 1) * n)::(ldK + 1)] += (- REG_EPS)
        lapack.sytrf(K, ipiv)
        def solve(x, y, z):
            blas.copy(x, u)
            blas.copy(y, u, offsety=n)
            scale(z, W, trans='T', inverse='I')
            pack(z, u, dims, mnl, offsety=(n + p))
            lapack.sytrs(K, ipiv, u)
            blas.copy(u, x, n=n)
            blas.copy(u, y, offsetx=n, n=p)
            unpack(u, z, dims, mnl, offsetx=(n + p))
        return solve
    return factor