Update app.py

app.py

@@ -56,7 +56,19 @@ def build_prompt(message, history, system_message, max_ctx_tokens=1024):
             msgs.append({"role": "assistant", "content": a})
     msgs.append({"role": "user", "content": message})
     while True:
-        text = tokenizer.apply_chat_template(msgs, tokenize=False, add_generation_prompt=True)
+        chat_template = """{% for m in messages %}
+        {{ m['role'] }}: {{ m['content'] }}
+        {% endfor %}
+        Assistant:"""
+        
+        text = tokenizer.apply_chat_template(
+            msgs,
+            chat_template=chat_template,
+            tokenize=False,
+            add_generation_prompt=True
+        )
+
+
         if len(tokenizer(text, add_special_tokens=False).input_ids) <= max_ctx_tokens:
             return text
         for i in range(1, len(msgs)):