tokenization.py

from transformers import PreTrainedTokenizerFast

class SinglePOTokenizer(PreTrainedTokenizerFast):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)

    def get_context(
        self,
        raw_instruction,
        rule_description,
    ):
        prompt = "You are an expert prompt engineer." + " "
        prompt += "Please help me optimize this prompt to get better response:\n\n[The Start of Raw Prompt]\n{}\n[The End of Raw Prompt]".format(raw_instruction)
        prompt += "\n\nYou should optimize this prompt by {}".format(rule_description)
        
        context = self.apply_chat_template(
            [
                {
                    "role": "user",
                    "content": prompt,
                }
            ],
            add_generation_prompt=True,
            tokenize=False,
        ) + "The Optimized Prompt:\n\n[The Start of Optimized Prompt"

        return context

    def parse_output(
        self,
        output_text,
        raw_instruction = "", # recommend to provide, so when some error happened, we can still use the raw instruction
    ):
        better_instruction = "The Optimized Prompt:\n\n[The Start of Optimized Prompt" + output_text
        
        if "[The Start of Optimized Prompt]" in better_instruction:
            better_instruction = better_instruction[better_instruction.index("[The Start of Optimized Prompt]") + len("[The Start of Optimized Prompt]"):]
            if better_instruction.startswith("\n"):
                better_instruction = better_instruction[1:]
        if "[The End of Optimized Prompt]" in better_instruction:
            better_instruction = better_instruction[:better_instruction.index("[The End of Optimized Prompt]")]
            if better_instruction.endswith("\n"):
                better_instruction = better_instruction[:-1]
        if "The Optimized Prompt:" in better_instruction: # almost error happened
            better_instruction = better_instruction[:better_instruction.index("The Optimized Prompt:")]
        
        if better_instruction.strip() == "": # some error may happen in optimization, so use the raw instruction
            better_instruction = raw_instruction

        if "The Optimized" in better_instruction: # still some error happened
            better_instruction = raw_instruction

        return better_instruction