update

module5.ipynb

@@ -515,12 +515,35 @@
     "print(test_results)"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## The Try-Except concept"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
    "metadata": {},
    "outputs": [],
-   "source": []
+   "source": [
+    "#!/usr/bin/env python3\n",
+    "def character_frequency(filename):\n",
+    "  \"\"\"Counts the frequency of each character in the given file.\"\"\"\n",
+    "  # First try to open the file\n",
+    "  try:\n",
+    "    f = open(filename)\n",
+    "  except OSError:\n",
+    "    return None\n",
+    "  # Now process the file\n",
+    "  characters = {}\n",
+    "  for line in f:\n",
+    "    for char in line:\n",
+    "      characters[char] = characters.get(char, 0) + 1\n",
+    "  f.close() \n",
+    "  return characters"
+   ]
   }
  ],
  "metadata": {