Hook STDOUT writes (this includes the print function) and print a stacktrace to see where the call originated.

hook_stdout.py

import inspect
import sys


def hook_stdout():
    """
    Hook STDOUT writes & print stacktrace.
    Useful for figuring out where a printed statement comes from.

    :return:
    """

    def add_stacktrace(func):
        def decorated(*args):
            # Get info about stack frames            
            curframe = inspect.currentframe()
            calframe = inspect.getouterframes(curframe)

            # Create a stacktrace (do not include `decorated` function)
            stacktrace = list(map(lambda c: '{} - {} - {}'.format(c.filename, c.lineno, c.function), calframe))[1:]
            stacktrace = 'Stacktrace\n{}\n{}\n\n'.format('_' * 100, '\n'.join(stacktrace))

            # Indicate original input
            original_input = ' '.join([*args])
            original_input = 'Original Input -> {}{}'.format(original_input, '\n' * 4)

            # Decorate original input with stacktrace
            decorated_input = '{}{}'.format(stacktrace, original_input)

            # Run original function with decorated input
            return func(decorated_input)

        return decorated
    
    sys.stdout.write = add_stacktrace(sys.stdout.write)


if __name__ == '__main__':
    hook_stdout()
    
    def func_a():
        def func_b():
            def func_c():
                # NOTE: `print` calls sys.stdout.write twice:
                #        - once for text content
                #        - once for newline character (`\n`)
                print('Hello World!')
                
            func_c()
        func_b()
    func_a()
    
"""
Example output:

    Stacktrace
    ____________________________________________________________________________________________________
    C:/Users/Stefan/Desktop/Python/STDOUT/hook_stdout.py - 45 - func_c
    C:/Users/Stefan/Desktop/Python/STDOUT/hook_stdout.py - 47 - func_b
    C:/Users/Stefan/Desktop/Python/STDOUT/hook_stdout.py - 49 - func_a
    C:/Users/Stefan/Desktop/Python/STDOUT/hook_stdout.py - 52 - <module>

    Original Input -> Hello World!



    Stacktrace
    ____________________________________________________________________________________________________
    C:/Users/Stefan/Desktop/Python/STDOUT/hook_stdout.py - 45 - func_c
    C:/Users/Stefan/Desktop/Python/STDOUT/hook_stdout.py - 47 - func_b
    C:/Users/Stefan/Desktop/Python/STDOUT/hook_stdout.py - 49 - func_a
    C:/Users/Stefan/Desktop/Python/STDOUT/hook_stdout.py - 52 - <module>

    Original Input -> 
"""