Issue #15610: The PyImport_ImportModuleEx macro now calls
PyImport_ImportModuleLevel() with a 'level' of 0 instead of -1 as the
latter is no longer a valid value.

Also added a versionchanged note for PyImport_ImportModuleLevel() just
in case people don't make the connection between changes to
__import__() and this C function.
diff --git a/Include/import.h b/Include/import.h
index bc21ae2..fdc2733 100644
--- a/Include/import.h
+++ b/Include/import.h
@@ -62,7 +62,7 @@
     );
 
 #define PyImport_ImportModuleEx(n, g, l, f) \
-    PyImport_ImportModuleLevel(n, g, l, f, -1)
+    PyImport_ImportModuleLevel(n, g, l, f, 0)
 
 PyAPI_FUNC(PyObject *) PyImport_GetImporter(PyObject *path);
 PyAPI_FUNC(PyObject *) PyImport_Import(PyObject *name);