diff --git a/tools/sparklog.ipynb b/tools/sparklog.ipynb
index 753710aca..4e5d9059e 100644
--- a/tools/sparklog.ipynb
+++ b/tools/sparklog.ipynb
@@ -692,9 +692,9 @@
     "                    for c in keys:\n",
     "                        v=columns[c]\n",
     "                        if v.startswith(\"array\") or v.startswith(\"map\") or v.startswith(\"struct\"):\n",
-    "                            s[1]=re.sub(c, '<span style=\"color:red;background-color:yellow\">'+html.escape(v)+\"</span>\",s[1])\n",
+    "                            s[1]=re.sub(re.escape(c), '<span style=\"color:red;background-color:yellow\">'+html.escape(v)+\"</span>\",s[1])\n",
     "                        else:\n",
-    "                            s[1]=re.sub(c, \"<font color=#33cc33>\"+html.escape(v)+\"</font>\",s[1])\n",
+    "                            s[1]=re.sub(re.escape(c), \"<font color=#33cc33>\"+html.escape(v)+\"</font>\",s[1])\n",
     "\n",
     "\n",
     "            htmls=['''<table style=\"table-layout:fixed;max-width: 100%;\">''']\n",
@@ -743,9 +743,9 @@
     "                    for c in keys:\n",
     "                        v=columns[c]\n",
     "                        if v.startswith(\"array\") or v.startswith(\"map\") or v.startswith(\"struct\"):\n",
-    "                            f[idx]=re.sub(c, '<span style=\"color:red;background-color:yellow\">'+html.escape(v)+\"</span>\",f[idx])\n",
+    "                            f[idx]=re.sub(re.escape(c), '<span style=\"color:red;background-color:yellow\">'+html.escape(v)+\"</span>\",f[idx])\n",
     "                        else:\n",
-    "                            f[idx]=re.sub(c, \"<font color=#33cc33>\"+html.escape(v)+\"</font>\",f[idx])\n",
+    "                            f[idx]=re.sub(re.escape(c), \"<font color=#33cc33>\"+html.escape(v)+\"</font>\",f[idx])\n",
     "            funchtml=\"<table>\"\n",
     "            for k,v in functions.items():\n",
     "                if shownops is not None:\n",