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Diffstat (limited to '.venv/lib/python3.12/site-packages/tokenizers/implementations/char_level_bpe.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/tokenizers/implementations/char_level_bpe.py | 150 |
1 files changed, 150 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/tokenizers/implementations/char_level_bpe.py b/.venv/lib/python3.12/site-packages/tokenizers/implementations/char_level_bpe.py new file mode 100644 index 00000000..29ca5977 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/tokenizers/implementations/char_level_bpe.py @@ -0,0 +1,150 @@ +from typing import Dict, Iterator, List, Optional, Tuple, Union + +from .. import AddedToken, Tokenizer, decoders, pre_tokenizers, trainers +from ..models import BPE +from ..normalizers import BertNormalizer, Lowercase, Sequence, unicode_normalizer_from_str +from .base_tokenizer import BaseTokenizer + + +class CharBPETokenizer(BaseTokenizer): + """Original BPE Tokenizer + + Represents the BPE algorithm, as introduced by Rico Sennrich + (https://arxiv.org/abs/1508.07909) + + The defaults settings corresponds to OpenAI GPT BPE tokenizers and differs from the original + Sennrich subword-nmt implementation by the following options that you can deactivate: + - adding a normalizer to clean up the text (deactivate with `bert_normalizer=False`) by: + * removing any control characters and replacing all whitespaces by the classic one. + * handle chinese chars by putting spaces around them. + * strip all accents. + - spitting on punctuation in addition to whitespaces (deactivate it with + `split_on_whitespace_only=True`) + """ + + def __init__( + self, + vocab: Optional[Union[str, Dict[str, int]]] = None, + merges: Optional[Union[str, Dict[Tuple[int, int], Tuple[int, int]]]] = None, + unk_token: Union[str, AddedToken] = "<unk>", + suffix: str = "</w>", + dropout: Optional[float] = None, + lowercase: bool = False, + unicode_normalizer: Optional[str] = None, + bert_normalizer: bool = True, + split_on_whitespace_only: bool = False, + ): + if vocab is not None and merges is not None: + tokenizer = Tokenizer( + BPE( + vocab, + merges, + dropout=dropout, + unk_token=str(unk_token), + end_of_word_suffix=suffix, + ) + ) + else: + tokenizer = Tokenizer(BPE(unk_token=str(unk_token), dropout=dropout, end_of_word_suffix=suffix)) + + if tokenizer.token_to_id(str(unk_token)) is not None: + tokenizer.add_special_tokens([str(unk_token)]) + + # Check for Unicode normalization first (before everything else) + normalizers = [] + + if unicode_normalizer: + normalizers += [unicode_normalizer_from_str(unicode_normalizer)] + + if bert_normalizer: + normalizers += [BertNormalizer(lowercase=False)] + + if lowercase: + normalizers += [Lowercase()] + + # Create the normalizer structure + if len(normalizers) > 0: + if len(normalizers) > 1: + tokenizer.normalizer = Sequence(normalizers) + else: + tokenizer.normalizer = normalizers[0] + + if split_on_whitespace_only: + tokenizer.pre_tokenizer = pre_tokenizers.WhitespaceSplit() + else: + tokenizer.pre_tokenizer = pre_tokenizers.BertPreTokenizer() + + tokenizer.decoder = decoders.BPEDecoder(suffix=suffix) + + parameters = { + "model": "BPE", + "unk_token": unk_token, + "suffix": suffix, + "dropout": dropout, + "lowercase": lowercase, + "unicode_normalizer": unicode_normalizer, + "bert_normalizer": bert_normalizer, + "split_on_whitespace_only": split_on_whitespace_only, + } + + super().__init__(tokenizer, parameters) + + @staticmethod + def from_file(vocab_filename: str, merges_filename: str, **kwargs): + vocab, merges = BPE.read_file(vocab_filename, merges_filename) + return CharBPETokenizer(vocab, merges, **kwargs) + + def train( + self, + files: Union[str, List[str]], + vocab_size: int = 30000, + min_frequency: int = 2, + special_tokens: List[Union[str, AddedToken]] = ["<unk>"], + limit_alphabet: int = 1000, + initial_alphabet: List[str] = [], + suffix: Optional[str] = "</w>", + show_progress: bool = True, + ): + """Train the model using the given files""" + + trainer = trainers.BpeTrainer( + vocab_size=vocab_size, + min_frequency=min_frequency, + special_tokens=special_tokens, + limit_alphabet=limit_alphabet, + initial_alphabet=initial_alphabet, + end_of_word_suffix=suffix, + show_progress=show_progress, + ) + if isinstance(files, str): + files = [files] + self._tokenizer.train(files, trainer=trainer) + + def train_from_iterator( + self, + iterator: Union[Iterator[str], Iterator[Iterator[str]]], + vocab_size: int = 30000, + min_frequency: int = 2, + special_tokens: List[Union[str, AddedToken]] = ["<unk>"], + limit_alphabet: int = 1000, + initial_alphabet: List[str] = [], + suffix: Optional[str] = "</w>", + show_progress: bool = True, + length: Optional[int] = None, + ): + """Train the model using the given iterator""" + + trainer = trainers.BpeTrainer( + vocab_size=vocab_size, + min_frequency=min_frequency, + special_tokens=special_tokens, + limit_alphabet=limit_alphabet, + initial_alphabet=initial_alphabet, + end_of_word_suffix=suffix, + show_progress=show_progress, + ) + self._tokenizer.train_from_iterator( + iterator, + trainer=trainer, + length=length, + ) |