In Willy Douhard's bigquery cookbook example - missing to_openai() method

[johnlabuyfoy1024]

I have configured Google Cloud successfully however, when I ran the bigquery Python example from the Cookbook with my first text question, I get the following error:
2024-04-30 14:17:52 - 'dict' object has no attribute 'to_openai'
Traceback (most recent call last):
File "C:\Users\johnl\PycharmProjects\bigquery\vnew\Lib\site-packages\chainlit\utils.py", line 39, in wrapper
return await user_function(**params_values)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\johnl\PycharmProjects\bigquery\app.py", line 139, in main
await chain(message.content)
File "C:\Users\johnl\PycharmProjects\bigquery\vnew\Lib\site-packages\chainlit\step.py", line 84, in async_wrapper
result = await func(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\johnl\PycharmProjects\bigquery\app.py", line 131, in chain
sql_query = await gen_query(human_query)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\johnl\PycharmProjects\bigquery\vnew\Lib\site-packages\chainlit\step.py", line 84, in async_wrapper
result = await func(*args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\johnl\PycharmProjects\bigquery\app.py", line 57, in gen_query
messages=[m.to_openai() for m in current_step.generation.messages],
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "C:\Users\johnl\PycharmProjects\bigquery\app.py", line 57, in
messages=[m.to_openai() for m in current_step.generation.messages],
^^^^^^^^^^^
AttributeError: 'dict' object has no attribute 'to_openai'

From this code snippet:

# Call OpenAI and stream the message
stream_resp = await openai_client.chat.completions.create(
    messages=[m.to_openai() for m in current_step.generation.messages],
    stream=True,
    **settings
)

Any help would be appreciated - I like this example very much! Please advise & thanks.