def _build_translation_inputs(
        self, raw_inputs, return_tensors: str, src_lang: Optional[str], tgt_lang: Optional[str], **extra_kwargs
    ):
        """Used by translation pipeline, to prepare inputs for the generate function"""
        if src_lang is None or tgt_lang is None:
            raise ValueError("Translation requires a `src_lang` and a `tgt_lang` for this model")
        self.src_lang = self._convert_lang_code_special_format(src_lang)
        self.tgt_lang = self._convert_lang_code_special_format(tgt_lang)
        inputs = self(raw_inputs, add_special_tokens=True, return_tensors=return_tensors, **extra_kwargs)
        tgt_lang_id = self.convert_tokens_to_ids(self.tgt_lang)
        inputs["forced_bos_token_id"] = tgt_lang_id
        return inputs
Used by translation pipeline, to prepare inputs for the generate function
dpkd/transformers/src/transformers/models/plbart/tokenization_plbart.py