updated streaming code

app.py

@@ -20,7 +20,7 @@ marketing_email_prompt = """Below is a product and description, please write a m
 {}"""
 
 def greet(product,description):
-    response = llm.create_chat_completion(
+    output = llm.create_chat_completion(
     messages=[
         {
             "role": "system",
@@ -40,9 +40,10 @@ def greet(product,description):
     stream=True
     )
     partial_message = ""
-    for chunk in response:
-        if chunk['choices'][0]['delta']['content'] is not None:
-            partial_message = partial_message + chunk['choices'][0]['delta'].get('content', '')
+    for chunk in output:
+        delta = chunk['choices'][0]['delta']
+        if 'content' in delta:
+            partial_message = partial_message + delta.get('content', '')
             yield partial_message
 
 demo = gr.Interface(fn=greet, inputs=["text","text"], outputs="text")