Can't import functions/modules

Question

I'm simply trying to import a function from another script. But despite import running successfully, the functions never enter my local environment.

The paths and files look like this:

project/__main__.py

project/script_a.py

from setup import script_b
x = ABC() # NameError: name 'ABC' is not defined
print(x)

project/setup/__init__.py

project/setup/script_b.py

def ABC():
    return "ABC"   

I've done this before and the documentation (officials and on here) is quite straightforward but I cannot grasp what I am failing to understand. Is the function running but never entering my environment?

---

I also tried using...

if __name__ == '__main__':
    def ABC():
        return "ABC"

...as script_b.