def build_tomo_curcuit_core(Q_program, qreg, creg):
    """Prepare quantum state for tomography reconstruction.
    The state could be arbitrary.

    """
    # Example state with 3 qubits.
    circuit_name = 'tomo_c'
    my_circuit = Q_program.create_circuit(circuit_name, [qreg], [creg])
    my_circuit.h(qreg[0])
    my_circuit.cx(qreg[0], qreg[1])
    my_circuit.cx(qreg[0], qreg[2])

    my_circuit.cx(qreg[1], qreg[0])
    my_circuit.y(qreg[0])

    my_circuit.h(qreg[2])
    my_circuit.cx(qreg[2], qreg[0])

    return my_circuit