Add clarifying information & remove mention of mock server, format

Author: simonkurtz-MSFT

labs/backend-pool-load-balancing/README.MD

@@ -4,7 +4,7 @@
 
 [![flow](../../images/backend-pool-load-balancing.gif)](backend-pool-load-balancing.ipynb)
 
-Playground to try the built-in load balancing [backend pool functionality of APIM](https://learn.microsoft.com/azure/api-management/backends?tabs=bicep) to either a list of Azure OpenAI endpoints or mock servers.
+Playground to try the built-in load balancing [backend pool functionality of APIM](https://learn.microsoft.com/azure/api-management/backends?tabs=bicep) to a list of Azure OpenAI endpoints.
 
 ### Result
 

labs/backend-pool-load-balancing/backend-pool-load-balancing.ipynb

@@ -9,12 +9,13 @@
     "## Backend pool Load Balancing lab\n",
     "![flow](../../images/backend-pool-load-balancing.gif)\n",
     "\n",
-    "Playground to try the built-in load balancing [backend pool functionality of APIM](https://learn.microsoft.com/azure/api-management/backends?tabs=bicep) to either a list of Azure OpenAI endpoints.\n",
+    "Playground to try the built-in load balancing [backend pool functionality of APIM](https://learn.microsoft.com/azure/api-management/backends?tabs=bicep) to a list of Azure OpenAI endpoints.\n",
     "\n",
     "Notes:\n",
-    "- The backend pool uses round-robin by default\n",
-    "- Priority and weight-based routing are also supported: Adjust the `priority` (the lower the number, the higher the priority) and `weight` parameters in the `openai_resources` variable\n",
-    "- The `retry` API Management policy initiates a retry to an available backend if an HTTP 429 status code is encountered\n",
+    "- **This is a typical prioritized PTU with fallback consumption scenario**. The lab specifically showcases how a priority 1 (highest) backend is exhausted before gracefully falling back to two equally-weighted priority 2 backends. \n",
+    "- The backend pool uses round-robin by default.\n",
+    "- Priority and weight-based routing are supported and can be adjusted by modifying `priority` (the lower the number, the higher the priority) and `weight` parameters in the `openai_resources` variable below.\n",
+    "- The `retry` API Management policy initiates a retry to an available backend if an HTTP 429 status code is encountered. This is transparent to the caller.\n",
     "\n",
     "### Result\n",
     "![result](result.png)\n",
@@ -132,7 +133,7 @@
     "with open(\"policy.xml\", 'r') as policy_xml_file:\n",
     "    policy_template_xml = policy_xml_file.read()\n",
     "    if \"{backend-id}\" in policy_template_xml:\n",
-    "        policy_xml = policy_template_xml.replace(\"{backend-id}\", str(\"openai-backend-pool\" if len(openai_resources) > 1 else openai_resources[0].get(\"name\")))                \n",
+    "        policy_xml = policy_template_xml.replace(\"{backend-id}\", str(\"openai-backend-pool\" if len(openai_resources) > 1 else openai_resources[0].get(\"name\")))\n",
     "    policy_xml_file.close()\n",
     "if policy_xml is not None:\n",
     "    open(\"policy.xml\", 'w').write(policy_xml)\n",
@@ -152,12 +153,12 @@
     "    }\n",
     "}\n",
     "\n",
-    "# write the parameters to a file \n",
+    "# write the parameters to a file\n",
     "with open('params.json', 'w') as bicep_parameters_file:\n",
     "    bicep_parameters_file.write(json.dumps(bicep_parameters))\n",
     "\n",
     "# run the deployment\n",
-    "output = utils.run(f\"az deployment group create --name {deployment_name} --resource-group {resource_group_name} --template-file main.bicep --parameters params.json\", \n",
+    "output = utils.run(f\"az deployment group create --name {deployment_name} --resource-group {resource_group_name} --template-file main.bicep --parameters params.json\",\n",
     "                f\"Deployment '{deployment_name}' succeeded\", f\"Deployment '{deployment_name}' failed\")\n",
     "open(\"policy.xml\", 'w').write(policy_template_xml)\n",
     "\n"
@@ -370,7 +371,7 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 3",
+   "display_name": ".venv",
    "language": "python",
    "name": "python3"
   },
@@ -384,7 +385,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.12.8"
+   "version": "3.12.0"
   }
  },
  "nbformat": 4,