Fix bug in example (best_model) (#161)

Co-authored-by: Marius Birkenbach <birkenbach@fzi.de>

Author: m-birke

examples/cars segmentation (camvid).ipynb

@@ -868,7 +868,7 @@
     "    gt_mask = gt_mask.squeeze()\n",
     "    \n",
     "    x_tensor = torch.from_numpy(image).to(DEVICE).unsqueeze(0)\n",
-    "    pr_mask = model.predict(x_tensor)\n",
+    "    pr_mask = best_model.predict(x_tensor)\n",
     "    pr_mask = (pr_mask.squeeze().cpu().numpy().round())\n",
     "        \n",
     "    visualize(\n",