diff --git a/Introduction to PyTorch for former Torchies.ipynb b/Introduction to PyTorch for former Torchies.ipynb
index 0a03004e822..a512f41b030 100644
--- a/Introduction to PyTorch for former Torchies.ipynb	
+++ b/Introduction to PyTorch for former Torchies.ipynb	
@@ -448,6 +448,7 @@
     "\n",
     "# this would fail if we didn't specify \n",
     "# that we want to retain variables\n",
+    "y.backward(gradient)\n",
     "z.backward(gradient)\n",
     "\n",
     "x.grad"