class importlib.machinery.BuiltinImporter
An importer for built-in modules. All known built-in modules are listed in sys.builtin_module_names. This class implements the importlib.abc.MetaPathFinder and importlib.abc.InspectLoader ABCs.
Only class methods are defined by this class to alleviate the need for instantiation.
Changed in version 3.5: As part of PEP 489, the builtin importer now implements Loader.create_module() and Loader.exec_module()