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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 define_rho_vector(rho, Ne):
 u"""Define the vectorized density matrix. ⎡ ρ₂₂ ⎤ ⎢ ⎥ ⎢ ρ₃₃ ⎥ ⎢ ⎥ ⎢re(ρ₂₁)⎥ ⎢ ⎥ ⎢re(ρ₃₁)⎥ ⎢ ⎥ ⎢re(ρ₃₂)⎥ ⎢ ⎥ ⎢im(ρ₂₁)⎥ ⎢ ⎥ ⎢im(ρ₃₁)⎥ ⎢ ⎥ ⎣im(ρ₃₂)⎦ """

    rho_vect = []
    for mu in range(1, Ne**2):
        i, j, s = IJ(mu, Ne)
        i = i-1; j = j-1
        rho_vect += [part_symbolic(rho[i, j], s)]
    return Matrix(rho_vect)