fix: empty system prompt

tokenization_minicpm.py

@@ -4,6 +4,7 @@ import keyword
 import traceback
 import uuid
 from collections import deque
+from copy import deepcopy
 from logging import getLogger
 from typing import Any, Dict, List, Optional, Union
 
@@ -324,6 +325,8 @@ def input_format(messages: List[Dict], tools: List[Dict], add_to_system=True):
             the tools list you can use
             For example:
     """
+    messages = deepcopy(messages)
+    tools = deepcopy(tools)
     if tools is not None and len(tools) > 0:
         header = (
             "from enum import Enum\nfrom typing import List, Dict, Optional\nfrom pydantic import BaseModel, Field\n\n"
@@ -363,8 +366,6 @@ func2(params)
         tools_string = ""
 
     if add_to_system:
-        if len(messages) > 0 and messages[0]["role"] != "system":
-            messages.insert(0, {"role": "system", "content": ""})
         return [message_format(msg, system_suffix=tools_string, user_prefix="") for msg in messages]
     else:
         return [message_format(msg, system_suffix="", user_prefix=tools_string) for msg in messages]