fix liteLLM proxy

cookbook/proxy-server/test_proxy_stream.py

@@ -0,0 +1,21 @@
+import openai
+import os
+
+os.environ["OPENAI_API_KEY"] = ""
+
+openai.api_key = os.environ["OPENAI_API_KEY"]
+openai.api_base ="http://localhost:5000"
+
+messages = [
+    {
+        "role": "user",
+        "content": "write a 1 pg essay in liteLLM"
+    }
+]
+
+response = openai.ChatCompletion.create(model="gpt-3.5-turbo", messages=messages, stream=True)
+print("got response", response)
+# response is a generator
+
+for chunk in response:
+    print(chunk)