SF bug [#466173] unpack TypeError unclear
Replaced 3 instances of "iter() of non-sequence" with
"iteration over non-sequence".
Restored "unpack non-sequence" for stuff like "a, b = 1".
diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index b8a4593..e5e7dcd 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -3261,7 +3261,7 @@
 	PyErr_Clear();
 	func = lookup_method(self, "__getitem__", &getitem_str);
 	if (func == NULL) {
-		PyErr_SetString(PyExc_TypeError, "iter() of non-sequence");
+		PyErr_SetString(PyExc_TypeError, "iteration over non-sequence");
 		return NULL;
 	}
 	Py_DECREF(func);