Update app.py

app.py

@@ -40,6 +40,8 @@ model = HfApiModel(
 # Import tool from Hub
 image_generation_tool = load_tool("agents-course/text-to-image", trust_remote_code=True)
 
+prompt_templates = {}  
+
 with open("prompts.yaml", 'r') as stream:
     try:
         system_prompt = yaml.safe_load(stream)