Improper way of setting up unitary with customized initial value

[Ye2018]

The code

# Set the initial unitary using the result from the previous example.
opts = {"initial_unitary": np.array([[ 1,  1],
                                     [-1, 1]]/np.sqrt(2))}

# Execute and obtain Unitary matrix of the circuit
result = execute(qc_init, simulator, backend_options=opts).result()

doesn't work any more.
We should use:

qc_init.set_unitary( np.array([[1, 1], 
                             [-1, 1]]/np.sqrt(2)))

to set up the initial value.