diff --git a/notebooks/texture_nca_grafting.ipynb b/notebooks/texture_nca_grafting.ipynb
index 6880e9a..30e6a66 100644
--- a/notebooks/texture_nca_grafting.ipynb
+++ b/notebooks/texture_nca_grafting.ipynb
@@ -238,6 +238,8 @@
         "id": "ewXnAPrbHx0-"
       },
       "source": [
+        "import os\n",
+        "\n",
         "#@title Minimalistic Neural CA\n",
         "ident = torch.tensor([[0.0,0.0,0.0],[0.0,1.0,0.0],[0.0,0.0,0.0]])\n",
         "sobel_x = torch.tensor([[-1.0,0.0,1.0],[-2.0,0.0,2.0],[-1.0,0.0,1.0]])\n",
@@ -521,4 +523,4 @@
       "outputs": []
     }
   ]
-}
\ No newline at end of file
+}