code: def file_ns_handler(importer, path_item, packageName, module):
      
  
      subpath = os.path.join(path_item, packageName.split('.')[-1])
      normalized = _normalize_cached(subpath)
      for item in module.__path__:
          if _normalize_cached(item) == normalized:
              break
      else:
          # Only return the path if it's not already there
          return subpath
docs: Compute an ns-package subpath for a filesystem or zipfile importer