Azure ML ExecutableNotFound: failed to execute PosixPath('dot'), make sure the Graphviz executables are on your systems' PATH

I am using LightGBM in Azure ML Jupyter notebooks, it works fine and I also installed graphviz.

However this line:

lgb.plot_tree(clf, tree_index = 1, figsize=(20,12))

throws this error:

ExecutableNotFound: failed to execute PosixPath('dot'), make sure the Graphviz executables are on your systems' PATH

>Solution :

Common problem (very common). There are two systems named Graphviz, and you need both!
see I'm getting this issue when trying to run the code I found on GitHub. Pydot and graphivz are installed but still getting this error