Python error in event handler: cannot import name 'json' from 'itsdangerous'

[Dave Stanke]

The event_handler service is throwing an error:

\ImportError: cannot import name 'json' from 'itsdangerous' (/usr/local/lib/python3.7/site-packages/itsdangerous/__init__.py)

According to the internet, this can be solved by updating Flask to 2.x.