[ Python 常見問題 ] Build a Call graph in python including modules and functions?

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Question
I have a bunch of scripts to perform a task. And I really need to know the call graph of the project because it is very confusing. I am not able to execute the code because it needs extra HW and SW to do so. However, I need to understand the logic behind it. So, I need to know if there is a tool (which does not require any python file execution) that can build a call graph using the modules instead of the trace or python parser.

I have such tools for C but not for python. Thank you.

HowTo
You might want to check out pycallgraph: pycallgraph

Also in this link a more manual approach is described:
generating-call-graphs-for-understanding-and-refactoring-python-code

Let's look at a few examples to learn how. Consider we have below python files:
- xyz.py

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1. import random  
2.   
3. def message(name):  
4.   greeting = random.choice(['Hi', 'Hello', 'Aloha'])  
5.   return f"{greeting}, {name}"  

- haha.py

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1. from xyz import *  
2.   
3. def say_hi(name):  
4.   print(message(name))  

- main.py

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1. from haha import say_hi  
2.   
3. if __name__ == '__main__':  
4.   say_hi('John')  

Usage example1 - command line
You can refer to here for more usage. Below is a simple example to generate call graph:

# pycallgraph graphviz --output-file=main.png -- ./main.py
Hello, John

Below graph will be generated:


Usage example2 - exclude unwanted nodes
Let's create a py file to list unwanted nodes as below:
- main_with_config.py

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1. #!/usr/bin/env python  
2. from haha import say_hi  
3. from pycallgraph import PyCallGraph  
4. from pycallgraph import Config  
5. from pycallgraph import GlobbingFilter  
6. from pycallgraph.output import GraphvizOutput  
7.   
8. config = Config()  
9. config.trace_filter = GlobbingFilter(exclude=[  
10.     # 'xyz.*',  
11.     # '*.secret_function',  
12. ])  
13.   
14. if __name__ == '__main__':  
15.   graphviz = GraphvizOutput(output_file='main_with_config.png')  
16.   
17.   with PyCallGraph(output=graphviz, config=config):  
18.     say_hi("John")  

This time you can obtain a clean chart: