add fallbacks tutorial to docs

docs/my-website/docs/tutorials/fallbacks.md

@@ -0,0 +1,47 @@
+Using completion() with Fallbacks for Reliability
+
+This tutorial demonstrates how to employ the `completion()` function with model fallbacks to ensure reliability. LLM APIs can be unstable, completion() with fallbacks ensures you'll always get a response from your calls
+
+## Usage 
+To use fallback models with `completion()`, specify a list of models in the `fallbacks` parameter. 
+
+Example
+```python
+try:
+    response = completion(
+        model="bad-model",
+        messages=messages,
+        fallbacks=["gpt-3.5-turbo", "command-nightly"]
+    )
+```
+
+Output
+```
+Completion with 'bad-model': got exception Unable to map your input to a model. Check your input - {'model': 'bad-model'
+
+
+
+completion call gpt-3.5-turbo
+{
+  "id": "chatcmpl-7qTmVRuO3m3gIBg4aTmAumV1TmQhB",
+  "object": "chat.completion",
+  "created": 1692741891,
+  "model": "gpt-3.5-turbo-0613",
+  "choices": [
+    {
+      "index": 0,
+      "message": {
+        "role": "assistant",
+        "content": "I apologize, but as an AI, I do not have the capability to provide real-time weather updates. However, you can easily check the current weather in San Francisco by using a search engine or checking a weather website or app."
+      },
+      "finish_reason": "stop"
+    }
+  ],
+  "usage": {
+    "prompt_tokens": 16,
+    "completion_tokens": 46,
+    "total_tokens": 62
+  }
+}
+
+```

docs/my-website/sidebars.js

@@ -34,7 +34,7 @@ const sidebars = {
     {
       type: 'category',
       label: 'Tutorials',
-      items: ['tutorials/huggingface_tutorial', 'tutorials/TogetherAI_liteLLM'],
+      items: ['tutorials/huggingface_tutorial', 'tutorials/TogetherAI_liteLLM', 'tutorials/fallbacks'],
     },
     'token_usage',
     'stream',