diff --git a/doc/tutorials/svo_vasp/svo_notebook.ipynb b/doc/tutorials/svo_vasp/svo_notebook.ipynb
index bf544ed8..7462f910 100644
--- a/doc/tutorials/svo_vasp/svo_notebook.ipynb
+++ b/doc/tutorials/svo_vasp/svo_notebook.ipynb
@@ -312,7 +312,7 @@
     "    mpi.report('found {0:d} blocks of degenerate orbitals in shell {1:d}'.format(num_block_deg_orbs, i_sh))\n",
     "    for iblock in range(num_block_deg_orbs):\n",
     "        mpi.report('block {0:d} consists of orbitals:'.format(iblock))\n",
-    "        for keys in SK.deg_shells[i_sh][iblock].keys():\n",
+    "        for keys in list(SK.deg_shells[i_sh][iblock].keys()):\n",
     "            mpi.report('  '+keys)"
    ]
   },
@@ -335,21 +335,20 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 2",
+   "display_name": "Python 3",
    "language": "python",
-   "name": "python2"
+   "name": "python3"
   },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
-    "version": 2
+    "version": 3
    },
    "file_extension": ".py",
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython2",
-   "version": "2.7.15+"
+   "pygments_lexer": "ipython3"
   }
  },
  "nbformat": 4,