I've just been using Python "pseudocode" with good success. It's great for getting structured output from GPT3. Works less well with chat-fine tuned models, hopefully openai releases a simple instruct-tuned GPT4 instead of chat-tuned.

For instance, this prompt:

    best_artists = search(year=2014, genre="hip-hop")
    assert(len(best_artists) == 10)
    for i, artist in enumerate(best_artists):
        print(f"{i}. {artist}")

    Stdout: 

Yields this output:

    0. Kendrick Lamar
    1. Drake
    2. J. Cole
    3. Logic
    4. Childish Gambino
    5. Joey Bada$$
    6. Chance the Rapper
    7. Schoolboy Q
    8. Vince Staples
    9. Run the Jewels

Note how the `assert` is used to constrain the output. The `search` method is not defined but what it does is obvious so the LLM hallucinates its output.