[allowing system role for deep seek renderer] (#139)

Author: ruiqi-zhong

tinker_cookbook/renderers.py

@@ -627,11 +627,16 @@ class DeepSeekV3Renderer(Renderer):
     Format like this (no newlines between messages):
         <|begin_of_sentence|><|User|>What can you help me with?<|Assistant|><think>Thinking...</think>I can help you with...<|end_of_centence|>
     For no-think, just use <|Assistant|></think>
+    Deepseek renderer does not support the system role out of the box. You can set system_role_as_user to True to automatically convert the system role to the user role.
     """
 
+    def __init__(self, tokenizer: Tokenizer, system_role_as_user: bool = False):
+        super().__init__(tokenizer)
+        self.system_role_as_user = system_role_as_user
+
     def _render_message(self, message: Message) -> tuple[list[int], list[int], list[int]]:
         assert message.get("thinking") is None, "TODO: support CoT in DsV3 renderer"
-        if message["role"] == "user":
+        if message["role"] == "user" or (self.system_role_as_user and message["role"] == "system"):
             role_token = self._get_special_token("User")
         elif message["role"] == "assistant":
             role_token = self._get_special_token("Assistant")