how to understand from where a function call is made?

I am using TreeSitter to parse python code.

I need to understand check_files_in_directory is invoked from GPT4Readability.utils. I already captured all the function calls. I have to do this programatically.

But now I have to find out from which file check_files_in_directory is called. I am struggling to understand what would the logic to do it. Can anyone please suggest?

I have to implement this with a Tree sitter AST parser from scratch. I would appreciate links to proper resources, high-level logic. I am not looking for actual code implementation and instead high-level reasoning.

import os
from getpass import getpass
from GPT4Readability.utils import *
import importlib.resources as pkg_resources  


def generate_readme(root_dir, output_name, model):
    """Generates a README.md file based on the python files in the provided directory

    Args:
        root_dir (str): The root directory of the python package to parse and generate a readme for
    """

    # prompt_folder_name = os.path.join(os.path.dirname(__file__), "prompts")
    # prompt_path = os.path.join(prompt_folder_name, "readme_prompt.txt")

    with pkg_resources.open_text('GPT4Readability.prompts','readme_prompt.txt') as f:         
        inb_msg = f.read()

    # with open(prompt_path) as f:
    #     lines = f.readlines()
    # inb_msg = "".join(lines)

    file_check_result = check_files_in_directory(root_dir)

from how to understand from where a function call is made?