code: def _load_subclasses(package):
      
      global _explicit_subclasses
      from acorn.config import settings
      spack = settings(package)
      if spack is not None:
          if spack.has_section("subclass"):
              _explicit_subclasses.update(dict(spack.items("subclass")))
docs: Loads the subclass settings for the specified package so that we can
      decorate the classes correctly.