vqe.py

def vqe(qubitOp):
    backend = Aer.get_backend('statevector_simulator') # You can switch to different backends by providing the name of backend.
    seed = 50
    cobyla = COBYLA()
    cobyla.set_options(maxiter=1000)
    ry = TwoLocal(qubitOp.num_qubits, 'ry', 'cz', reps=3, entanglement='full')
    vqe = VQE(qubitOp, ry, cobyla)
    vqe.random_seed = seed
    quantum_instance = QuantumInstance(backend=backend, seed_simulator=seed, seed_transpiler=seed)
    result = vqe.run(quantum_instance)
    selection, state, values, probabilities = print_result(result)
    print(selection_to_picks(num_assets, selection))
    return state, values, probabilities