Solution 1
pip uninstall Flask Jinja2
pip install Flask Jinja2
pip freeze
click==8.0.4
Flask==2.0.3
itsdangerous==2.1.2
Jinja2==3.1.1
MarkupSafe==2.1.1
Werkzeug==2.0.3
Solution 2
>>> from jinja2.utils import markupsafe
>>> markupsafe.Markup()
Markup('')