How to debug a python module in VSCode

I use VSCode to develop python programs. Debugging python code in VSCode works great for normal scripts. But when I tried to debug code within a python module nothing happened. No ui changes to show debug controls and no terminal output. If you do python module development with VSCode, please take a look at my settings below and let me know what did I do wrong.

Thanks!

Module directory structure

.
└── MODULE
    ├── entrypoints
    │   ├── __init__.py
    │   ├── ...
    │   └── APP.py
    ├── ...
    └── some_script.py

VSCode debug launch.json file

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Run MODULE APP FUNCTION",
            "type": "python",
            "request": "launch",
            "module": "MODULE.entrypoints.APP",
            "args": [
                "FUNCTION",
                "input.txt",
                "output.txt"
            ],
            "console": "integratedTerminal",
            "justMyCode": true,
        }
    ]
}

Running in terminal

python2 -m MODULE.entrypoints.APP FUNCTION input.txt output.txt
Running FUNCTION:  |████████████████████████████████████████████████████████████████████████████████████████████████████| 100% 24/24