diff --git a/doc/user_guide/Serialization_and_Persistence.ipynb b/doc/user_guide/Serialization_and_Persistence.ipynb
index 971fbafb..a37d0e20 100644
--- a/doc/user_guide/Serialization_and_Persistence.ipynb
+++ b/doc/user_guide/Serialization_and_Persistence.ipynb
@@ -179,7 +179,7 @@
     "\n",
     "class P(param.Parameterized):\n",
     "    a = param.Integer(default=5, doc='Int', bounds=(2,30), inclusive_bounds=(True, False))\n",
-    "    e = param.List([1,2,3], class_=int)\n",
+    "    e = param.List([1,2,3], item_type=int)\n",
     "    g = param.Date(default=datetime.datetime.now())\n",
     "    l = param.Range(default=(1.1,2.3), bounds=(1,3))\n",
     "    m = param.String(default='baz', allow_None=True)\n",