ImportError: cannot import name 'safe_join'

[JuanjoSalvador]

While trying to run an example, I get this error. Looks like a deprecated version of Flask.

(venv) ➜  blask-dev python3 main.py 
Traceback (most recent call last):
  File "/home/juanjo/Documentos/blask-dev/main.py", line 1, in <module>
    from blask import BlaskApp
  File "/home/juanjo/Documentos/blask/venv/lib/python3.10/site-packages/blask-0.2.3-py3.10.egg/blask/__init__.py", line 20, in <module>
    from blask.blaskapp import BlaskApp
  File "/home/juanjo/Documentos/blask/venv/lib/python3.10/site-packages/blask-0.2.3-py3.10.egg/blask/blaskapp.py", line 19, in <module>
    from flask.helpers import safe_join
ImportError: cannot import name 'safe_join' from 'flask.helpers' (/home/juanjo/Documentos/blask/venv/lib/python3.10/site-packages/Flask-2.2.2-py3.10.egg/flask/helpers.py)