refactor conversation plucking in sharegpt

src/axolotl/prompt_tokenizers.py

@@ -268,6 +268,9 @@ class AlpacaReflectionPTStrategy(ReflectionPromptTokenizingStrategy):
 
 
 class ShareGPTPromptTokenizingStrategy(PromptTokenizingStrategy):
+    def get_conversation_thread(self, prompt):
+        return prompt["conversations"]
+
     def tokenize_prompt(self, prompt):
         result = {
             "input_ids": [],
@@ -279,7 +282,7 @@ class ShareGPTPromptTokenizingStrategy(PromptTokenizingStrategy):
         assistant_token = self._get_assistant_token()
         try:
             for i, part in enumerate(
-                self.prompter.build_prompt(prompt["conversations"])
+                self.prompter.build_prompt(self.get_conversation_thread(prompt))
             ):
                 if isinstance(part, tuple):
                     if part[0] == "USER:":