diff --git a/strings/validate_ip_address.ipynb b/strings/validate_ip_address.ipynb
index 767f274..167ebeb 100644
--- a/strings/validate_ip_address.ipynb
+++ b/strings/validate_ip_address.ipynb
@@ -14,7 +14,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 14,
+   "execution_count": 18,
    "metadata": {},
    "outputs": [],
    "source": [
@@ -46,14 +46,14 @@
     "        return False\n",
     "\n",
     "    for part in parts:\n",
-    "        if not validate_part(part):\n",
+    "        if not valid_part(part):\n",
     "            return False\n",
     "    return True"
    ]
   },
   {
    "cell_type": "code",
-   "execution_count": 15,
+   "execution_count": 19,
    "metadata": {},
    "outputs": [
     {
@@ -62,7 +62,7 @@
        "True"
       ]
      },
-     "execution_count": 15,
+     "execution_count": 19,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -73,7 +73,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 16,
+   "execution_count": 20,
    "metadata": {},
    "outputs": [
     {
@@ -82,7 +82,7 @@
        "False"
       ]
      },
-     "execution_count": 16,
+     "execution_count": 20,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -93,7 +93,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 17,
+   "execution_count": 21,
    "metadata": {},
    "outputs": [
     {
@@ -102,7 +102,7 @@
        "False"
       ]
      },
-     "execution_count": 17,
+     "execution_count": 21,
      "metadata": {},
      "output_type": "execute_result"
     }