Update conversation.py
diff --git a/fastchat/conversation.py b/fastchat/conversation.py
index 33387ad69e..c66ee18127 100644
--- a/fastchat/conversation.py
+++ b/fastchat/conversation.py
@@ -228,8 +228,7 @@ def to_gradio_chatbot(self):
 
     def to_openai_api_messages(self):
         """Convert the conversation to OpenAI chat completion format."""
-        system_prompt = self.system_template.format(system_message=self.system_message)
-        ret = [{"role": "system", "content": system_prompt}]
+        ret = [{"role": "system", "content": self.system_message}]
 
         for i, (_, msg) in enumerate(self.messages[self.offset :]):
             if i % 2 == 0:

OpenAI chat completion API does NOT require the prompt at the start of the `system` message (e.g., do not include `<|im_start|>system\n`) - just the system message itself.

Docs: https://platform.openai.com/docs/guides/gpt/chat-completions-api

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