Update app.py

app.py

@@ -16,7 +16,7 @@ def format_prompt(message, history):
   return prompt
 
 def generate(
-        prompt, system_prompt, temperature=0.9, max_new_tokens=256, top_p=0.95, repetition_penalty=1.0, history,
+        prompt, system_prompt, temperature=0.9, max_new_tokens=256, top_p=0.95, repetition_penalty=1.0, history="",
 ):
     system_prompt=prompts.WEB_DEV
     temperature = float(temperature)