when running codes below, VannaFlaskApp(vn).run() could not open browser. What's wrong?

!pip install vanna

from vanna.remote import VannaDefault
from vanna.flask import VannaFlaskApp

vn = VannaDefault(model='chinook', api_key='db883fa116504fc6888ed59453253a94')
vn.connect_to_sqlite('https://vanna.ai/Chinook.sqlite')
vn.ask('What are the top 10 artists by sales?')

VannaFlaskApp(vn).run()