Demonstration of a custom python package resource loader

supplychain-interdiction.py

# Needed for defining the finder
import importlib.machinery

# Needed to add our hook to the meta_path hook list
import sys

# To debug with pdb.set_trace() be sure to import the following before adding the meta_path
import pdb
import readline

class MyMetaPathFinder(importlib.machinery.PathFinder): 
    @classmethod 
    def find_spec(cls, fullname, path=None, target=None): 
        spec = super(MyMetaPathFinder, cls).find_spec(fullname, path, target) 
        if spec is not None: 
            def foo(path): 
                return b'5' 
            spec.loader.get_data = foo 
        return spec 

# Installing our hook
sys.meta_path.insert(0, MyMetaPathFinder)

# Could have imported this above, more of a nothing up my sleeves that it still imports packages as necessary
import pkgutil

# Return a value from a non-existent package resource 
assert b'5' = pkgutil.get_data('wheel', 'foobar')