fix: api helper func chapter 2

Author: geemi725

.gitignore

@@ -41,6 +41,8 @@ share/python-wheels/
 .installed.cfg
 *.egg
 MANIFEST
+chapter_2/.env
+chapter_3/.env
 
 # PyInstaller
 #  Usually these files are written by a python script from a template

chapter_2/llms_for_biology.ipynb

@@ -100,6 +100,8 @@
         "        return userdata.get('OPENAI_API_KEY')\n",
         "    except ImportError:\n",
         "        # Not in Colab — fall back to environment variable\n",
+        "        from dotenv import load_dotenv\n",
+        "        load_dotenv()\n",
         "        api_key = os.environ.get('OPENAI_API_KEY')\n",
         "        if not api_key:\n",
         "            raise ValueError(\n",
@@ -144,14 +146,13 @@
       "source": [
         "\n",
         "from openai import OpenAI\n",
-        "from google.colab import userdata\n",
         "\n",
         "# Access the OpenAI API key\n",
-        "openai_api_key = userdata.get('OPENAI_API_KEY')\n",
+        "openai_api_key = get_api_key()\n",
         "# Tell the OpenAI client to use your API key\n",
         "client = OpenAI(api_key=openai_api_key)\n",
         "# LLM model to generate answer. Replace model name if deprecated\n",
-        "LLM_MODEL = \"gpt-4.1-nano-2025-04-14\"\n",
+        "LLM_MODEL = \"gpt-5.5\"\n",
         "# Add your question here\n",
         "QUESTION = \"What is the difference between Machine Learning and Deep Learning?\" \n",
         "\n",
@@ -573,11 +574,21 @@
       "provenance": []
     },
     "kernelspec": {
-      "display_name": "Python 3",
-      "name": "python3"
+      "display_name": "tutorials",
+      "language": "python",
+      "name": "fh-fellows-tutorials"
     },
     "language_info": {
-      "name": "python"
+      "codemirror_mode": {
+        "name": "ipython",
+        "version": 3
+      },
+      "file_extension": ".py",
+      "mimetype": "text/x-python",
+      "name": "python",
+      "nbconvert_exporter": "python",
+      "pygments_lexer": "ipython3",
+      "version": "3.12.5"
     }
   },
   "nbformat": 4,