Fixed compilation error introduced in 745fd5550bc0.
diff --git a/Modules/_elementtree.c b/Modules/_elementtree.c
index 62b7ede..35643a7 100644
--- a/Modules/_elementtree.c
+++ b/Modules/_elementtree.c
@@ -1260,7 +1260,7 @@
 }
 
 static int
-element_setitem(PyObject* self_, Py_ssize_t index, PyObject* item)
+element_setitem(PyObject* self_, Py_ssize_t index_, PyObject* item)
 {
     ElementObject* self = (ElementObject*) self_;
     int i, index;