diff --git a/hera_notebook_templates/notebooks/lststack.ipynb b/hera_notebook_templates/notebooks/lststack.ipynb
index d482747..ed5dde5 100644
--- a/hera_notebook_templates/notebooks/lststack.ipynb
+++ b/hera_notebook_templates/notebooks/lststack.ipynb
@@ -497,6 +497,23 @@
     "print(f\"This data {'is' if data_is_redundantly_averaged else 'is not'} redundantly averaged.\")"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "6bc8380a-775c-4d77-9049-60e308e246db",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# A partial function that makes it simpler to create files of the correct format.\n",
+    "get_fname = partial(\n",
+    "    lstbin.io.format_outfile_name,\n",
+    "    lst=stackconf.lst_grid_edges[0],\n",
+    "    pols=stackconf.pols,\n",
+    "    inpaint_mode=True,\n",
+    "    lst_branch_cut=stackconf.properties[\"lst_branch_cut\"],\n",
+    ")"
+   ]
+  },
   {
    "cell_type": "markdown",
    "id": "8dcb2696",
@@ -795,13 +812,9 @@
     "        all_calibration_parameters[stackconf.lst_grid[i]] = calibration_parameters\n",
     "        \n",
     "    # Get the calibration filename\n",
-    "    cal_fname = lstbin.io.format_outfile_name(\n",
-    "        lst=stackconf.lst_grid_edges[0],\n",
-    "        pols=stackconf.pols,\n",
-    "        fname_format=fname_format.replace(\"sum.uvh5\", \"lstcal.pkl\"),\n",
-    "        inpaint_mode=True,\n",
-    "        lst_branch_cut=stackconf.properties[\"lst_branch_cut\"],\n",
-    "        kind=\"LST\"\n",
+    "    cal_fname = get_fname(\n",
+    "        fname_format=fname_format.replace(\"{blchunk}\", \"{blchunk:03}\").replace(\".sum.uvh5\", \".pkl\"),\n",
+    "        kind='LSTCAL',\n",
     "    )\n",
     "    outfile = outdir / cal_fname\n",
     "        \n",
@@ -1356,17 +1369,8 @@
     "\n",
     "create_file = partial(\n",
     "    lstbin.io.create_lstbin_output_file,\n",
-    "#    uvd_template=uvd_template,\n",
     "    outdir=outdir,\n",
     "    overwrite=overwrite,\n",
-    ")\n",
-    "\n",
-    "get_fname = partial(\n",
-    "    lstbin.io.format_outfile_name,\n",
-    "    lst=stackconf.lst_grid_edges[0],\n",
-    "    pols=stackconf.pols,\n",
-    "    inpaint_mode=True,\n",
-    "    lst_branch_cut=stackconf.properties[\"lst_branch_cut\"],\n",
     ")"
    ]
   },