Note that the mimetypes.MimeTypes class was added in Python 2.2.
diff --git a/Doc/lib/libmimetypes.tex b/Doc/lib/libmimetypes.tex
index 3801109..327b2ba 100644
--- a/Doc/lib/libmimetypes.tex
+++ b/Doc/lib/libmimetypes.tex
@@ -113,6 +113,8 @@
 
   The optional \var{filenames} parameter can be used to cause
   additional files to be loaded ``on top'' of the default database.
+
+  \versionadded{2.2}
 \end{classdesc}