you have to install it with quote :

pip install "sqlalchemy-iris[intersystems]"

Btw, if you want to avoid conflict between Embedded Python, Community driver and Official one, you can use iris embedded python wrapper :

pip install iris-embedded-python-wrapper

in your case you have to. force-reinstall it :

pip install https://github.com/intersystems-community/intersystems-irispython/releases/download/3.9.2/intersystems_iris-3.9.2-py3-none-any.whl --upgrade --force-reinstall
pip install iris-embedded-python-wrapper --upgrade --force-reinstall

hi @Muhammad Waseem 

I bet the issue is due to a conflict with iris official driver.

Embedded python and iris official driver share the same module name iris.

But the official driver obviously doesn't include the cls attribute.

To solve this issue please for install this module :

pip install iris-embedded-python-wrapper --upgrade

This module is an helper to play with embedded python with a native python interpreter not only irispython.