Update app.py

app.py

@@ -60,7 +60,7 @@ def chat(message,
 
     if model == "zephyr_7b":
         model = zephyr_7b
-    elif model == "llama_7b"
+    elif model == "llama_7b":
         model = llama_7b
     elif model == "llama_13b":
         model == llama_13b