Reformat openai proxy setting as code (#5330)

# Reformat the openai proxy setting as code


  Only affect the doc for openai Model
  - @hwchase17
  - @agola11

docs/modules/models/llms/integrations/openai.ipynb

@@ -133,7 +133,16 @@
    "id": "58a9ddb1",
    "metadata": {},
    "source": [
-    "# if you are behind an explicit proxy, you can use the OPENAI_PROXY environment variable to pass through\n",
+    "If you are behind an explicit proxy, you can use the OPENAI_PROXY environment variable to pass through"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "55142cec",
+   "metadata": {},
+   "outputs": [],
+   "source": [
     "os.environ[\"OPENAI_PROXY\"] = \"http://proxy.yourcompany.com:8080\""
    ]
   }