Just running the main.py locally works. Referencing a sub folder as a module tree: `- test` `- - __init__.py` `- - base.py` `- main.py` in main.py: `from test import base` `def some_function():` ` base.testFunc()` `if __name__ == "__main__":` ` some_function()` When deploying the function, or when running emulators locally with `firebase emulators:start` `ModuleNotFoundError: No module named 'test'` When running `python main.py` everything works as expected