I'm following this documentation of the anytree package to render the graph. Please note I have installed Graphviz on my Mac using:

pip3 install graphviz

When I try to execute this,

RenderTreeGraph(udo).to_picture("udo.png")

I’m getting the following errors:

Traceback (most recent call last):
File "", line 1, in
RenderTreeGraph(udo).to_picture("udo.png")
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site-packages/anytree/dotexport.py", line 51, in to_picture
check_call(cmd)
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/subprocess.py", line 286, in check_call
retcode = call(*popenargs, **kwargs)
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/subprocess.py", line 267, in call
with Popen(*popenargs, **kwargs) as p:
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/subprocess.py", line 707, in init
restore_signals, start_new_session)
File "/Library/Frameworks/Python.framework/Versions/3.6/lib/python3.6/subprocess.py", line 1326, in _execute_child
raise child_exception_type(errno_num, err_msg)
FileNotFoundError: [Errno 2] No such file or directory: 'dot'

How can I render the tree?