09_git.ipynb: 'try' and '%time' line magic do not work together

For some reason using %time line magic inside `try:` ... `except` ...
block did not work.

Hopefully this change would fix CI errors (PyArrow not installed).

Author: jnareb

09_git.ipynb

@@ -2772,26 +2772,55 @@
      "name": "stdout",
      "output_type": "stream",
      "text": [
-      "Wall time: 6.8 s\n",
-      "Wall time: 5.26 s\n",
-      "Wall time: 345 ms\n",
-      "Wall time: 674 ms\n",
-      "Wall time: 672 ms\n"
+      "pickle.gz:  Wall time: 6.77 s\n",
+      "csv.gz:     Wall time: 5.45 s\n",
+      "hdf (full): Wall time: 664 ms\n",
+      "hdf (appd): Wall time: 840 ms\n"
      ]
     }
    ],
    "source": [
+    "print('pickle.gz: ', end=' ', flush=True)\n",
     "%time graph_info_df.to_pickle('datasets/git-commit_graph.info.pickle.gz')\n",
+    "print('csv.gz:    ', end=' ', flush=True)\n",
     "%time graph_info_df.to_csv('datasets/git-commit_graph.info.csv.gz')\n",
-    "try:\n",
-    "    #%time graph_info_df.to_feather('datasets/git-commit_graph.df_edgelist.feather')\n",
-    "    %time graph_info_df.to_parquet('datasets/git-commit_graph.info.parquet')\n",
-    "except ImportError:\n",
-    "    print(\"Missing optional dependency 'pyarrow' required\")\n",
+    "print('hdf (full):', end=' ', flush=True)\n",
     "%time graph_info_df.to_hdf('datasets/git-commit_graph.info.hdf5', 'df', mode='w', complevel=6)\n",
+    "print('hdf (appd):', end=' ', flush=True)\n",
     "%time graph_info_df.to_hdf('datasets/git-commit_graph.hdf5', 'df_info', mode='a', complevel=6)"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# feather does not support non-numerical index, IIRC\n",
+    "#%time graph_info_df.to_feather('datasets/git-commit_graph.info.feather')"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Wall time: 423 ms\n"
+     ]
+    }
+   ],
+   "source": [
+    "%%time\n",
+    "try:\n",
+    "    graph_info_df.to_parquet('datasets/git-commit_graph.info.parquet')\n",
+    "except ImportError:\n",
+    "    print(\"Missing optional dependency 'pyarrow' required\")"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,