diff --git a/diffphys-code-burgers.ipynb b/diffphys-code-burgers.ipynb
index f0f9791..a85c704 100644
--- a/diffphys-code-burgers.ipynb
+++ b/diffphys-code-burgers.ipynb
@@ -32,7 +32,7 @@
    },
    "outputs": [],
    "source": [
-    "#!pip install --upgrade --quiet phiflow==2.2\n",
+    "!pip install --upgrade --quiet phiflow==2.2\n",
     "from phi.tf.flow import *\n",
     "\n",
     "N = 128\n",