Hmm... better add a version annotation for the Iterator Protocol section.
diff --git a/Doc/api/api.tex b/Doc/api/api.tex
index b441c4a..07a2263 100644
--- a/Doc/api/api.tex
+++ b/Doc/api/api.tex
@@ -2092,6 +2092,8 @@
 
 \section{Iterator Protocol \label{iterator}}
 
+\versionadded{2.2}
+
 There are only a couple of functions specifically for working with
 iterators.