Rename importlib.util.set___package__ to set_package.
diff --git a/Lib/importlib/util.py b/Lib/importlib/util.py
index 2b6154b..9022ab8 100644
--- a/Lib/importlib/util.py
+++ b/Lib/importlib/util.py
@@ -1,3 +1,3 @@
 """Utility code for constructing importers, etc."""
 from ._bootstrap import module_for_loader
-from ._bootstrap import set___package__
+from ._bootstrap import set_package