Issue #14646: __import__() now sets __loader__ if need be.

importlib.util.module_for_loader also will set __loader__ along with
__package__. This is in conjunction to a forthcoming update to PEP 302
which will make these two attributes required for loaders to set.
diff --git a/Python/importlib.h b/Python/importlib.h
index cc3ddc4..e9f5faf 100644
--- a/Python/importlib.h
+++ b/Python/importlib.h
Binary files differ