Raise TypeError if the name given to importlib.__import__() lacks an rpartition
attribute. Was throwing AttributeError before. Discovered when running
test_builtin against importlib.

This exception change is specific to importlib.__import__() and does not apply to
import_module() as it is being done for compatibility reasons only.
diff --git a/Misc/NEWS b/Misc/NEWS
index d6d7dc3..6f73e73 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -68,6 +68,10 @@
 Library
 -------
 
+- Raise a TypeError when the name of a module to be imported for
+  importlib.__import__ is not a string (was raising an
+  AttributeError before).
+
 - Allow the fromlist passed into importlib.__import__ to be any iterable.
 
 - Have importlib raise ImportError if None is found in sys.modules.