codingutf8 2022 the facebook ai research team s and the huggingface inc team licensed under the apache license version 2 0 the license you may not use this file except in compliance with the license you may obtain a copy of the license at http www apache orglicenseslicense2 0 unless required by applicable law or agreed to in writing software distributed under the license is distributed on an as is basis without warranties or conditions of any kind either express or implied see the license for the specific language governing permissions and limitations under the license construct a fast nllb tokenizer backed by huggingface s tokenizers library based on bpehttps huggingface codocstokenizerspythonlatestcomponents html highlightbpemodels this tokenizer inherits from pretrainedtokenizerfast which contains most of the main methods users should refer to this superclass for more information regarding those methods the tokenization method is tokens eos language code for source language documents and language code tokens eos for target language documents examples python from transformers import nllbtokenizerfast tokenizer nllbtokenizerfast frompretrained facebooknllb200distilled600m srclangenglatn tgtlangfralatn exampleenglishphrase un chief says there is no military solution in syria expectedtranslationfrench le chef de l onu affirme qu il n y a pas de solution militaire en syrie inputs tokenizerexampleenglishphrase texttargetexpectedtranslationfrench returntensorspt args vocabfile str path to the vocabulary file bostoken str optional defaults to s the beginning of sequence token that was used during pretraining can be used a sequence classifier token tip when building a sequence using special tokens this is not the token that is used for the beginning of sequence the token used is the clstoken tip eostoken str optional defaults to s the end of sequence token tip when building a sequence using special tokens this is not the token that is used for the end of sequence the token used is the septoken tip septoken str optional defaults to s the separator token which is used when building a sequence from multiple sequences e g two sequences for sequence classification or for a text and a question for question answering it is also used as the last token of a sequence built with special tokens clstoken str optional defaults to s the classifier token which is used when doing sequence classification classification of the whole sequence instead of pertoken classification it is the first token of the sequence when built with special tokens unktoken str optional defaults to unk the unknown token a token that is not in the vocabulary cannot be converted to an id and is set to be this token instead padtoken str optional defaults to pad the token used for padding for example when batching sequences of different lengths masktoken str optional defaults to mask the token used for masking values this is the token used when training this model with masked language modeling this is the token which the model will try to predict tokenizerfile str optional the path to a tokenizer file to use instead of the vocab file srclang str optional the language to use as source language for translation tgtlang str optional the language to use as target language for translation mask token behave like a normal word i e include the space before it only add those special tokens if they are not already there build model inputs from a sequence or a pair of sequence for sequence classification tasks by concatenating and adding special tokens the special tokens depend on calling setlang an nllb sequence has the following format where x represents the sequence inputids for encoder x eos srclangcode decoderinputids for decoder x eos tgtlangcode bos is never used pairs of sequences are not the expected use case but they will be handled without a separator args tokenids0 listint list of ids to which the special tokens will be added tokenids1 listint optional optional second list of ids for sequence pairs returns listint list of input ids glossaryinputids with the appropriate special tokens we don t expect to process pairs but leave the pair logic for api consistency create a mask from the two sequences passed to be used in a sequencepair classification task nllb does not make use of token type ids therefore a list of zeros is returned args tokenids0 listint list of ids tokenids1 listint optional optional second list of ids for sequence pairs returns listint list of zeros used by translation pipeline to prepare inputs for the generate function if srclang is none or tgtlang is none raise valueerrortranslation requires a srclang and a tgtlang for this model self srclang srclang inputs selfrawinputs addspecialtokenstrue returntensorsreturntensors extrakwargs tgtlangid self converttokenstoidstgtlang inputsforcedbostokenid tgtlangid return inputs def prepareseq2seqbatch self srctexts liststr srclang str englatn tgttexts optionalliststr none tgtlang str fralatn kwargs batchencoding self srclang srclang self tgtlang tgtlang return super prepareseq2seqbatchsrctexts tgttexts kwargs def switchtoinputmodeself return self setsrclangspecialtokensself srclang def switchtotargetmodeself return self settgtlangspecialtokensself tgtlang def setsrclangspecialtokensself srclang none self curlangcode self converttokenstoidssrclang if self legacybehaviour self prefixtokens self suffixtokens self eostokenid self curlangcode else self prefixtokens self curlangcode self suffixtokens self eostokenid prefixtokensstr self convertidstotokensself prefixtokens suffixtokensstr self convertidstotokensself suffixtokens self tokenizer postprocessor processors templateprocessing singleprefixtokensstr a suffixtokensstr pairprefixtokensstr a b suffixtokensstr specialtokenslistzipprefixtokensstr suffixtokensstr self prefixtokens self suffixtokens def settgtlangspecialtokensself lang str none self curlangcode self converttokenstoidslang if self legacybehaviour self prefixtokens self suffixtokens self eostokenid self curlangcode else self prefixtokens self curlangcode self suffixtokens self eostokenid prefixtokensstr self convertidstotokensself prefixtokens suffixtokensstr self convertidstotokensself suffixtokens self tokenizer postprocessor processors templateprocessing singleprefixtokensstr a suffixtokensstr pairprefixtokensstr a b suffixtokensstr specialtokenslistzipprefixtokensstr suffixtokensstr self prefixtokens self suffixtokens def savevocabularyself savedirectory str filenameprefix optionalstr none tuplestr if not self cansaveslowtokenizer raise valueerror your fast tokenizer does not have the necessary information to save the vocabulary for a slow tokenizer if not os path isdirsavedirectory logger errorfvocabulary path savedirectory should be a directory return outvocabfile os path join savedirectory filenameprefix if filenameprefix else vocabfilesnamesvocabfile if os path abspathself vocabfile os path abspathoutvocabfile copyfileself vocabfile outvocabfile return outvocabfile coding utf 8 2022 the facebook ai research team s and the huggingface inc team licensed under the apache license version 2 0 the license you may not use this file except in compliance with the license you may obtain a copy of the license at http www apache org licenses license 2 0 unless required by applicable law or agreed to in writing software distributed under the license is distributed on an as is basis without warranties or conditions of any kind either express or implied see the license for the specific language governing permissions and limitations under the license fmt skip construct a fast nllb tokenizer backed by huggingface s tokenizers library based on bpe https huggingface co docs tokenizers python latest components html highlight bpe models this tokenizer inherits from pretrainedtokenizerfast which contains most of the main methods users should refer to this superclass for more information regarding those methods the tokenization method is tokens eos language code for source language documents and language code tokens eos for target language documents examples python from transformers import nllbtokenizerfast tokenizer nllbtokenizerfast from_pretrained facebook nllb 200 distilled 600m src_lang eng_latn tgt_lang fra_latn example_english_phrase un chief says there is no military solution in syria expected_translation_french le chef de l onu affirme qu il n y a pas de solution militaire en syrie inputs tokenizer example_english_phrase text_target expected_translation_french return_tensors pt args vocab_file str path to the vocabulary file bos_token str optional defaults to s the beginning of sequence token that was used during pretraining can be used a sequence classifier token tip when building a sequence using special tokens this is not the token that is used for the beginning of sequence the token used is the cls_token tip eos_token str optional defaults to s the end of sequence token tip when building a sequence using special tokens this is not the token that is used for the end of sequence the token used is the sep_token tip sep_token str optional defaults to s the separator token which is used when building a sequence from multiple sequences e g two sequences for sequence classification or for a text and a question for question answering it is also used as the last token of a sequence built with special tokens cls_token str optional defaults to s the classifier token which is used when doing sequence classification classification of the whole sequence instead of per token classification it is the first token of the sequence when built with special tokens unk_token str optional defaults to unk the unknown token a token that is not in the vocabulary cannot be converted to an id and is set to be this token instead pad_token str optional defaults to pad the token used for padding for example when batching sequences of different lengths mask_token str optional defaults to mask the token used for masking values this is the token used when training this model with masked language modeling this is the token which the model will try to predict tokenizer_file str optional the path to a tokenizer file to use instead of the vocab file src_lang str optional the language to use as source language for translation tgt_lang str optional the language to use as target language for translation mask token behave like a normal word i e include the space before it only add those special tokens if they are not already there build model inputs from a sequence or a pair of sequence for sequence classification tasks by concatenating and adding special tokens the special tokens depend on calling set_lang an nllb sequence has the following format where x represents the sequence input_ids for encoder x eos src_lang_code decoder_input_ids for decoder x eos tgt_lang_code bos is never used pairs of sequences are not the expected use case but they will be handled without a separator args token_ids_0 list int list of ids to which the special tokens will be added token_ids_1 list int optional optional second list of ids for sequence pairs returns list int list of input ids glossary input ids with the appropriate special tokens we don t expect to process pairs but leave the pair logic for api consistency create a mask from the two sequences passed to be used in a sequence pair classification task nllb does not make use of token type ids therefore a list of zeros is returned args token_ids_0 list int list of ids token_ids_1 list int optional optional second list of ids for sequence pairs returns list int list of zeros used by translation pipeline to prepare inputs for the generate function reset the special tokens to the source lang setting in legacy mode no prefix and suffix eos src_lang_code in default mode prefix src_lang_code suffix eos reset the special tokens to the target lang setting in legacy mode no prefix and suffix eos tgt_lang_code in default mode prefix tgt_lang_code suffix eos
import os
from shutil import copyfile
from typing import List, Optional, Tuple

from tokenizers import processors

from ...tokenization_utils import AddedToken, BatchEncoding
from ...tokenization_utils_fast import PreTrainedTokenizerFast
from ...utils import is_sentencepiece_available, logging


if is_sentencepiece_available():
    from .tokenization_nllb import NllbTokenizer
else:
    NllbTokenizer = None


logger = logging.get_logger(__name__)


VOCAB_FILES_NAMES = {"vocab_file": "sentencepiece.bpe.model", "tokenizer_file": "tokenizer.json"}

PRETRAINED_VOCAB_FILES_MAP = {
    "vocab_file": {
        "facebook/nllb-200-distilled-600M": (
            "https://huggingface.co/facebook/nllb-200-distilled-600M/resolve/main/sentencepiece.bpe.model"
        ),
    },
    "tokenizer_file": {
        "facebook/nllb-200-distilled-600M": (
            "https://huggingface.co/facebook/nllb-200-distilled-600M/resolve/main/tokenizer.json"
        ),
    },
}

PRETRAINED_POSITIONAL_EMBEDDINGS_SIZES = {
    "facebook/nllb-large-en-ro": 1024,
    "facebook/nllb-200-distilled-600M": 1024,
}

FAIRSEQ_LANGUAGE_CODES = ['ace_Arab', 'ace_Latn', 'acm_Arab', 'acq_Arab', 'aeb_Arab', 'afr_Latn', 'ajp_Arab', 'aka_Latn', 'amh_Ethi', 'apc_Arab', 'arb_Arab', 'ars_Arab', 'ary_Arab', 'arz_Arab', 'asm_Beng', 'ast_Latn', 'awa_Deva', 'ayr_Latn', 'azb_Arab', 'azj_Latn', 'bak_Cyrl', 'bam_Latn', 'ban_Latn', 'bel_Cyrl', 'bem_Latn', 'ben_Beng', 'bho_Deva', 'bjn_Arab', 'bjn_Latn', 'bod_Tibt', 'bos_Latn', 'bug_Latn', 'bul_Cyrl', 'cat_Latn', 'ceb_Latn', 'ces_Latn', 'cjk_Latn', 'ckb_Arab', 'crh_Latn', 'cym_Latn', 'dan_Latn', 'deu_Latn', 'dik_Latn', 'dyu_Latn', 'dzo_Tibt', 'ell_Grek', 'eng_Latn', 'epo_Latn', 'est_Latn', 'eus_Latn', 'ewe_Latn', 'fao_Latn', 'pes_Arab', 'fij_Latn', 'fin_Latn', 'fon_Latn', 'fra_Latn', 'fur_Latn', 'fuv_Latn', 'gla_Latn', 'gle_Latn', 'glg_Latn', 'grn_Latn', 'guj_Gujr', 'hat_Latn', 'hau_Latn', 'heb_Hebr', 'hin_Deva', 'hne_Deva', 'hrv_Latn', 'hun_Latn', 'hye_Armn', 'ibo_Latn', 'ilo_Latn', 'ind_Latn', 'isl_Latn', 'ita_Latn', 'jav_Latn', 'jpn_Jpan', 'kab_Latn', 'kac_Latn', 'kam_Latn', 'kan_Knda', 'kas_Arab', 'kas_Deva', 'kat_Geor', 'knc_Arab', 'knc_Latn', 'kaz_Cyrl', 'kbp_Latn', 'kea_Latn', 'khm_Khmr', 'kik_Latn', 'kin_Latn', 'kir_Cyrl', 'kmb_Latn', 'kon_Latn', 'kor_Hang', 'kmr_Latn', 'lao_Laoo', 'lvs_Latn', 'lij_Latn', 'lim_Latn', 'lin_Latn', 'lit_Latn', 'lmo_Latn', 'ltg_Latn', 'ltz_Latn', 'lua_Latn', 'lug_Latn', 'luo_Latn', 'lus_Latn', 'mag_Deva', 'mai_Deva', 'mal_Mlym', 'mar_Deva', 'min_Latn', 'mkd_Cyrl', 'plt_Latn', 'mlt_Latn', 'mni_Beng', 'khk_Cyrl', 'mos_Latn', 'mri_Latn', 'zsm_Latn', 'mya_Mymr', 'nld_Latn', 'nno_Latn', 'nob_Latn', 'npi_Deva', 'nso_Latn', 'nus_Latn', 'nya_Latn', 'oci_Latn', 'gaz_Latn', 'ory_Orya', 'pag_Latn', 'pan_Guru', 'pap_Latn', 'pol_Latn', 'por_Latn', 'prs_Arab', 'pbt_Arab', 'quy_Latn', 'ron_Latn', 'run_Latn', 'rus_Cyrl', 'sag_Latn', 'san_Deva', 'sat_Beng', 'scn_Latn', 'shn_Mymr', 'sin_Sinh', 'slk_Latn', 'slv_Latn', 'smo_Latn', 'sna_Latn', 'snd_Arab', 'som_Latn', 'sot_Latn', 'spa_Latn', 'als_Latn', 'srd_Latn', 'srp_Cyrl', 'ssw_Latn', 'sun_Latn', 'swe_Latn', 'swh_Latn', 'szl_Latn', 'tam_Taml', 'tat_Cyrl', 'tel_Telu', 'tgk_Cyrl', 'tgl_Latn', 'tha_Thai', 'tir_Ethi', 'taq_Latn', 'taq_Tfng', 'tpi_Latn', 'tsn_Latn', 'tso_Latn', 'tuk_Latn', 'tum_Latn', 'tur_Latn', 'twi_Latn', 'tzm_Tfng', 'uig_Arab', 'ukr_Cyrl', 'umb_Latn', 'urd_Arab', 'uzn_Latn', 'vec_Latn', 'vie_Latn', 'war_Latn', 'wol_Latn', 'xho_Latn', 'ydd_Hebr', 'yor_Latn', 'yue_Hant', 'zho_Hans', 'zho_Hant', 'zul_Latn']  


class NllbTokenizerFast(PreTrainedTokenizerFast):
    

    vocab_files_names = VOCAB_FILES_NAMES
    max_model_input_sizes = PRETRAINED_POSITIONAL_EMBEDDINGS_SIZES
    pretrained_vocab_files_map = PRETRAINED_VOCAB_FILES_MAP
    model_input_names = ["input_ids", "attention_mask"]
    slow_tokenizer_class = NllbTokenizer

    prefix_tokens: List[int] = []
    suffix_tokens: List[int] = []

    def __init__(
        self,
        vocab_file=None,
        tokenizer_file=None,
        bos_token="<s>",
        eos_token="</s>",
        sep_token="</s>",
        cls_token="<s>",
        unk_token="<unk>",
        pad_token="<pad>",
        mask_token="<mask>",
        src_lang=None,
        tgt_lang=None,
        additional_special_tokens=None,
        legacy_behaviour=False,
        **kwargs,
    ):
        
        mask_token = (
            AddedToken(mask_token, normalized=True, lstrip=True, special=True)
            if isinstance(mask_token, str)
            else mask_token
        )
        self.legacy_behaviour = legacy_behaviour

        _additional_special_tokens = FAIRSEQ_LANGUAGE_CODES.copy()

        if additional_special_tokens is not None:
            
            _additional_special_tokens.extend(
                [t for t in additional_special_tokens if t not in _additional_special_tokens]
            )

        super().__init__(
            vocab_file=vocab_file,
            tokenizer_file=tokenizer_file,
            bos_token=bos_token,
            eos_token=eos_token,
            sep_token=sep_token,
            cls_token=cls_token,
            unk_token=unk_token,
            pad_token=pad_token,
            mask_token=mask_token,
            src_lang=src_lang,
            tgt_lang=tgt_lang,
            additional_special_tokens=_additional_special_tokens,
            legacy_behaviour=legacy_behaviour,
            **kwargs,
        )

        self.vocab_file = vocab_file

        self.lang_code_to_id = {
            lang_code: self.convert_tokens_to_ids(lang_code) for lang_code in FAIRSEQ_LANGUAGE_CODES
        }

        self._src_lang = src_lang if src_lang is not None else "eng_Latn"
        self.cur_lang_code = self.convert_tokens_to_ids(self._src_lang)
        self.tgt_lang = tgt_lang
        self.set_src_lang_special_tokens(self._src_lang)

    @property
    def can_save_slow_tokenizer(self) -> bool:
        return os.path.isfile(self.vocab_file) if self.vocab_file else False

    @property
    def src_lang(self) -> str:
        return self._src_lang

    @src_lang.setter
    def src_lang(self, new_src_lang: str) -> None:
        self._src_lang = new_src_lang
        self.set_src_lang_special_tokens(self._src_lang)

    def build_inputs_with_special_tokens(
        self, token_ids_0: List[int], token_ids_1: Optional[List[int]] = None
    ) -> List[int]:
        
        if token_ids_1 is None:
            return self.prefix_tokens + token_ids_0 + self.suffix_tokens
        
        return self.prefix_tokens + token_ids_0 + token_ids_1 + self.suffix_tokens

    def create_token_type_ids_from_sequences(
        self, token_ids_0: List[int], token_ids_1: Optional[List[int]] = None
    ) -> List[int]:
        

        sep = [self.sep_token_id]
        cls = [self.cls_token_id]

        if token_ids_1 is None:
            return len(cls + token_ids_0 + sep) * [0]
        return len(cls + token_ids_0 + sep + sep + token_ids_1 + sep) * [0]

    def _build_translation_inputs(
        self, raw_inputs, return_tensors: str, src_lang: Optional[str], tgt_lang: Optional[str], **extra_kwargs
    ):
        
        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 = src_lang
        inputs = self(raw_inputs, add_special_tokens=True, return_tensors=return_tensors, **extra_kwargs)
        tgt_lang_id = self.convert_tokens_to_ids(tgt_lang)
        inputs["forced_bos_token_id"] = tgt_lang_id
        return inputs

    def prepare_seq2seq_batch(
        self,
        src_texts: List[str],
        src_lang: str = "eng_Latn",
        tgt_texts: Optional[List[str]] = None,
        tgt_lang: str = "fra_Latn",
        **kwargs,
    ) -> BatchEncoding:
        self.src_lang = src_lang
        self.tgt_lang = tgt_lang
        return super().prepare_seq2seq_batch(src_texts, tgt_texts, **kwargs)

    def _switch_to_input_mode(self):
        return self.set_src_lang_special_tokens(self.src_lang)

    def _switch_to_target_mode(self):
        return self.set_tgt_lang_special_tokens(self.tgt_lang)

    def set_src_lang_special_tokens(self, src_lang) -> None:
        
        self.cur_lang_code = self.convert_tokens_to_ids(src_lang)

        if self.legacy_behaviour:
            self.prefix_tokens = []
            self.suffix_tokens = [self.eos_token_id, self.cur_lang_code]
        else:
            self.prefix_tokens = [self.cur_lang_code]
            self.suffix_tokens = [self.eos_token_id]

        prefix_tokens_str = self.convert_ids_to_tokens(self.prefix_tokens)
        suffix_tokens_str = self.convert_ids_to_tokens(self.suffix_tokens)

        self._tokenizer.post_processor = processors.TemplateProcessing(
            single=prefix_tokens_str + ["$A"] + suffix_tokens_str,
            pair=prefix_tokens_str + ["$A", "$B"] + suffix_tokens_str,
            special_tokens=list(zip(prefix_tokens_str + suffix_tokens_str, self.prefix_tokens + self.suffix_tokens)),
        )

    def set_tgt_lang_special_tokens(self, lang: str) -> None:
        
        self.cur_lang_code = self.convert_tokens_to_ids(lang)
        if self.legacy_behaviour:
            self.prefix_tokens = []
            self.suffix_tokens = [self.eos_token_id, self.cur_lang_code]
        else:
            self.prefix_tokens = [self.cur_lang_code]
            self.suffix_tokens = [self.eos_token_id]

        prefix_tokens_str = self.convert_ids_to_tokens(self.prefix_tokens)
        suffix_tokens_str = self.convert_ids_to_tokens(self.suffix_tokens)

        self._tokenizer.post_processor = processors.TemplateProcessing(
            single=prefix_tokens_str + ["$A"] + suffix_tokens_str,
            pair=prefix_tokens_str + ["$A", "$B"] + suffix_tokens_str,
            special_tokens=list(zip(prefix_tokens_str + suffix_tokens_str, self.prefix_tokens + self.suffix_tokens)),
        )

    def save_vocabulary(self, save_directory: str, filename_prefix: Optional[str] = None) -> Tuple[str]:
        if not self.can_save_slow_tokenizer:
            raise ValueError(
                "Your fast tokenizer does not have the necessary information to save the vocabulary for a slow "
                "tokenizer."
            )

        if not os.path.isdir(save_directory):
            logger.error(f"Vocabulary path ({save_directory}) should be a directory.")
            return
        out_vocab_file = os.path.join(
            save_directory, (filename_prefix + "-" if filename_prefix else "") + VOCAB_FILES_NAMES["vocab_file"]
        )

        if os.path.abspath(self.vocab_file) != os.path.abspath(out_vocab_file):
            copyfile(self.vocab_file, out_vocab_file)

        return (out_vocab_file,)