AttributeError: 'NoneType' object has no attribute 'questions'

[anechii]

I am getting an exception when running vn.ask on a linux server.

~ $ python
>>> import vanna
>>> from vanna.remote import VannaDefault
>>> vn = VannaDefault(model='chinook', api_key=vanna.get_api_key('[email protected]'))
>>> vn.connect_to_sqlite('https://vanna.ai/Chinook.sqlite')
>>> vn.ask('What are the top 10 artists by sales?')
'NoneType' object has no attribute 'questions'
(None, None, None)
>>> 

Is there a reason this code here returns a None value, inevitably causing this NoneType error ? What does it mean and how to prevent this from happening ? https://github.com/vanna-ai/vanna/blob/a72b842d420cf1fa061e5f97d45ea08051651ebb/src/vanna/vannadb/vannadb_vector.py#L190