parsing nested api responses — without crashing on a missing key

Write a function extract_content(response) that pulls the assistant's reply text out of an OpenAI/Anthropic-shaped response.

The chain you want is roughly: response["choices"][0]["message"]["content"]

Make it defensive:

• If choices is missing or empty, return the string "(no choices)".
• If message is missing on the first choice, return "(no message)".
• If content is missing, return "(no content)".
• Otherwise return the actual content string.

The starter has three test responses. Print the result for each.

Expected output:

hello world
(no choices)
(no content)