@classmethod
def _register_service_type(cls, subclass):
    """Registers subclass handlers of various service-type-specific service
           implementations. Look for classes decorated with
           @Folder._register_service_type for hints on how this works."""
    if hasattr(subclass, '__service_type__'):
        cls._service_type_mapping[subclass.__service_type__] = subclass
        if subclass.__service_type__:
            setattr(subclass, subclass.__service_type__, property(lambda x: x))
    return subclass
