diff --git a/content/15_python_toolkit.ipynb b/content/15_python_toolkit.ipynb
index c428885..377d729 100644
--- a/content/15_python_toolkit.ipynb
+++ b/content/15_python_toolkit.ipynb
@@ -12,7 +12,6 @@
    "cell_type": "markdown",
    "id": "2f23783a-0203-44bc-b0da-962ace70cf29",
    "metadata": {
-    "jp-MarkdownHeadingCollapsed": true,
     "tags": []
    },
    "source": [
@@ -98,7 +97,8 @@
     "    - [Tushar's Blog](https://tushar.lol/)\n",
     "    - [Simon Willison: TILs on python](https://til.simonwillison.net/python)\n",
     "    - [Software Design by Example](https://third-bit.com/sdxpy/)\n",
-    "    - [Python 3 Module of the Week](https://pymotw.com/3/)"
+    "    - [Python 3 Module of the Week](https://pymotw.com/3/)\n",
+    "    - [Pydon'ts](https://mathspp.com/blog/pydonts)"
    ]
   },
   {