diff --git a/notebooks/simple_example_3_manual_control.ipynb b/notebooks/simple_example_3_manual_control.ipynb
index 7f492e196d5cad28fb4f6251ba3a9b983980a5b4..951fa8953b732d00e993711259726596f95f7273 100644
--- a/notebooks/simple_example_3_manual_control.ipynb
+++ b/notebooks/simple_example_3_manual_control.ipynb
@@ -114,7 +114,7 @@
     "# Print the observation vector for agent 0\n",
     "obs, all_rewards, done, _ = env.step({0: 0})\n",
     "for i in range(env.get_num_agents()):\n",
-    "    env.obs_builder.util_print_obs_subtree(tree=obs[i], num_features_per_node=7)\n",
+    "    env.obs_builder.util_print_obs_subtree(tree=obs[i])\n",
     "\n",
     "env_renderer = RenderTool(env, gl=\"PIL\")\n",
     "# env_renderer = RenderTool(env, gl=\"PILSVG\")\n",
diff --git a/tox.ini b/tox.ini
index e93c522bb01912a5495367494ae59e76edc8e0e7..2047166aace141680561623c7edf4d11a2b4534f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -113,8 +113,6 @@ deps =
     -r{toxinidir}/requirements_dev.txt
     -r{toxinidir}/requirements_continuous_integration.txt
 commands =
-; install current version of flatland to be used by notebooks
-    sh -c 'python setup.py install'
 ; run tests from subfolder to ensure that resources are accessed via resources and not via relative paths
     sh -c 'mkdir -p {envtmpdir}/6f59bc68108c3895b1828abdd04b9a06'
     sh -c 'jupyter nbextension install --py --sys-prefix widgetsnbextension'