def normalizer(self, proto):
list_normalizers = [
normalizers.Replace("``", '"'),
normalizers.Replace("''", '"')
]
if not self.original_tokenizer.keep_accents:
list_normalizers.append(normalizers.NFKD())
list_normalizers.append(normalizers.StripAccents())
if self.original_tokenizer.do_lower_case:
list_normalizers.append(normalizers.Lowercase())
precompiled_charsmap = proto.normalizer_spec.precompiled_charsmap
list_normalizers.append(normalizers.Precompiled(precompiled_charsmap))
return normalizers.Sequence(list_normalizers)
def __init__(
self,
replacement: str = "▁",
add_prefix_space: bool = True,
unk_token: Union[str, AddedToken] = "<unk>",
eos_token: Union[str, AddedToken] = "</s>",
pad_token: Union[str, AddedToken] = "<pad>",
):
self.special_tokens = {
"pad": {"id": 0, "token": pad_token},
"eos": {"id": 1, "token": eos_token},
"unk": {"id": 2, "token": unk_token},
}
self.special_tokens_list = [None] * len(self.special_tokens)
for token_dict in self.special_tokens.values():
self.special_tokens_list[token_dict["id"]] = token_dict["token"]
tokenizer = Tokenizer(Unigram())
tokenizer.normalizer = normalizers.Sequence(
[
normalizers.Nmt(),
normalizers.NFKC(),
normalizers.Replace(Regex(" {2,}"), " "),
normalizers.Lowercase(),
]
)
tokenizer.pre_tokenizer = pre_tokenizers.Sequence(
[
pre_tokenizers.Metaspace(replacement=replacement, add_prefix_space=add_prefix_space),
pre_tokenizers.Digits(individual_digits=True),
pre_tokenizers.Punctuation(),
]
)
tokenizer.decoder = decoders.Metaspace(replacement=replacement, add_prefix_space=add_prefix_space)
tokenizer.post_processor = TemplateProcessing(
single=f"$A {self.special_tokens['eos']['token']}",
special_tokens=[(self.special_tokens["eos"]["token"], self.special_tokens["eos"]["id"])],
)
parameters = {
"model": "SentencePieceUnigram",
"replacement": replacement,
"add_prefix_space": add_prefix_space,
}
super().__init__(tokenizer, parameters)
def from_spm(filename: str):
try:
import sys
sys.path.append(".")
import sentencepiece_model_pb2 as model
except Exception:
raise Exception(
"You don't seem to have the required protobuf file, in order to use this function you need to run `pip install protobuf` and `wget https://raw.githubusercontent.com/google/sentencepiece/master/python/src/sentencepiece/sentencepiece_model_pb2.py` for us to be able to read the intrinsics of your spm_file. `pip install sentencepiece` is not required."
)
m = model.ModelProto()
m.ParseFromString(open(filename, "rb").read())
precompiled_charsmap = m.normalizer_spec.precompiled_charsmap
vocab = [(piece.piece, piece.score) for piece in m.pieces]
unk_id = m.trainer_spec.unk_id
model_type = m.trainer_spec.model_type
if model_type != 1:
raise Exception(
"You're trying to run a `Unigram` model but you're file was trained with a different algorithm"
)
replacement = "▁"
add_prefix_space = True
tokenizer = Tokenizer(Unigram(vocab, unk_id))
tokenizer.normalizer = normalizers.Sequence(
[
normalizers.Precompiled(precompiled_charsmap),
normalizers.Replace(Regex(" {2,}"), " "),
]
)
tokenizer.pre_tokenizer = pre_tokenizers.Metaspace(
replacement=replacement, add_prefix_space=add_prefix_space
)
tokenizer.decoder = decoders.Metaspace(
replacement=replacement, add_prefix_space=add_prefix_space
)
parameters = {
"model": "SentencePieceUnigram",
}
obj = BaseTokenizer.__new__(SentencePieceUnigramTokenizer, tokenizer, parameters)
BaseTokenizer.__init__(obj, tokenizer, parameters)
return obj
def _prepare_pipeline(self):
self.tokenizer.normalizer = normalizers.Sequence(
[NFD(), Lowercase(), StripAccents()])
self.tokenizer.pre_tokenizer = Whitespace()
self.tokenizer.post_processor = TemplateProcessing(
single="[CLS] $A [SEP]",
pair="[CLS] $A [SEP] $B:1 [SEP]:1",
special_tokens=[
("[CLS]", 1),
("[SEP]", 2),
],
)
self.tokenizer.enable_padding(
pad_id=self.__class__.SPECIAL_TOKENS.index("[PAD]"),
pad_token="[PAD]")
def main(args):
# from tokenizers import BertWordPieceTokenizer
from tokenizers import Tokenizer
from tokenizers.models import WordPiece
bert_tokenizer = Tokenizer(WordPiece())
# bert_tokenizer = Tokenizer(MBartTokenizer())
from tokenizers import normalizers
from tokenizers.normalizers import Lowercase, NFD, StripAccents
bert_tokenizer.normalizer = normalizers.Sequence(
[NFD(), Lowercase(), StripAccents()])
from tokenizers.pre_tokenizers import Whitespace
bert_tokenizer.pre_tokenizer = Whitespace()
# from tokenizers.processors import TemplateProcessing
#
# bert_tokenizer.post_processor = TemplateProcessing(
# single="[CLS] $A [SEP]",
# pair="[CLS] $A [SEP] $B:1 [SEP]:1",
# special_tokens=[
# ("[CLS]", 1),
# ("[SEP]", 2),
# ],
# )
from tokenizers.trainers import WordPieceTrainer
trainer = WordPieceTrainer(
vocab_size=10000,
special_tokens=["[UNK]", "[CLS]", "[PAD]",
"[MASK]"] # "[SEP]", "[PAD]", "[MASK]"]
)
files = glob.glob(args.text_raw_files_pattern)
bert_tokenizer.train(trainer, files)
os.makedirs(args.output_dir, exist_ok=True)
model_files = bert_tokenizer.model.save(args.output_dir,
"bert-tokenizer-kr")
bert_tokenizer.model = WordPiece.from_file(*model_files, unk_token="[UNK]")
bert_tokenizer.save(os.path.join(args.output_dir,
"bert-tokenizer-kr.json"))
def configure_tokenizers(self, padding, truncation, max_length, lower):
# Settings
pad_length = None
if padding in {True, "longest"}:
pass
elif padding in {"max_length"}:
pad_length = max_length
elif padding in {False, "do_not_pad"}:
pass
else:
raise ValueError("Unknown padding type")
# SRC tokenizer
tok_normalizers = [NFD(), Strip()]
if lower:
tok_normalizers += [Lowercase()]
self.tokenizer = Tokenizer(tok_model()) # unk_token=... not working
self.tokenizer.add_special_tokens(self.special_tokens)
self.tokenizer.pre_tokenizer = pre_tokenizers.Sequence(
[WhitespaceSplit()])
self.tokenizer.normalizer = normalizers.Sequence(
tok_normalizers) # StripAccents requires NFD
self.tokenizer.decoder = tok_decoder()
# Define template (Needed for the sos/eos tokens)
basic_template = TemplateProcessing(
single=f"{self.SOS_WORD} $A {self.EOS_WORD}",
pair=
f"{self.SOS_WORD} $A {self.EOS_WORD} {self.SOS_WORD} $B {self.EOS_WORD}",
special_tokens=[
(self.SOS_WORD, self.tokenizer.token_to_id(self.SOS_WORD)),
(self.EOS_WORD, self.tokenizer.token_to_id(self.EOS_WORD))
],
)
self.tokenizer.post_processor = basic_template
if padding:
self.tokenizer.enable_padding(pad_id=self.tokenizer.token_to_id(
self.PAD_WORD),
pad_token=self.PAD_WORD,
length=pad_length)
if truncation:
self.tokenizer.enable_truncation(max_length,
stride=0,
strategy='longest_first')
def train_tokenizer() -> Tuple[tokenizers.Tokenizer, Generator, int]:
tokenizer = tokenizers.Tokenizer(models.WordPiece(unk_token="<unk>"))
tokenizer.decoder = decoders.WordPiece()
tokenizer.normalizer = normalizers.Sequence([
normalizers.NFD(), # NFD unicode normalizer
normalizers.Lowercase(),
normalizers.StripAccents()
])
tokenizer.pre_tokenizer = tokenizers.pre_tokenizers.Sequence([
pre_tokenizers.Whitespace(),
pre_tokenizers.Digits(individual_digits=False)
])
tokenizer.post_processor = processors.TemplateProcessing(
single="$A </s>",
pair="$A </s> [SEP] <s> $B:1",
special_tokens=[("[SEP]", 1), ("<s>", 2), ("</s>", 3)])
dataset = datasets.load_dataset("wikitext",
"wikitext-103-raw-v1",
split="test")
def batch_iterator(batch_size=1000):
for i in range(0, len(dataset), batch_size):
yield dataset[i:i + batch_size]["text"]
tokenizer.train_from_iterator(
batch_iterator(),
trainer=trainers.WordPieceTrainer(
vocab_size=10000, special_tokens=["<unk>", "[SEP]", "<s>",
"</s>"]))
def generator():
for record in dataset:
if record['text'].strip() != '':
for sentence in sent_tokenizer(record['text']):
yield sentence
data = tf.data.Dataset.from_generator(generator,
output_signature=(tf.TensorSpec(
shape=(None), dtype=tf.string)))
data = data.map(tf.strings.strip,
num_parallel_calls=tf.data.experimental.AUTOTUNE)
return tokenizer, data
def converted(self) -> Tokenizer:
vocab = self.original_tokenizer.encoder
merges = list(self.original_tokenizer.bpe_ranks.keys())
unk_token = self.original_tokenizer.unk_token
tokenizer = Tokenizer(
BPE(
vocab=vocab,
merges=merges,
dropout=None,
continuing_subword_prefix="",
end_of_word_suffix="</w>",
fuse_unk=False,
unk_token=str(unk_token),
))
tokenizer.normalizer = normalizers.Sequence([
normalizers.NFC(),
normalizers.Replace(Regex(r"\s+"), " "),
normalizers.Lowercase()
])
tokenizer.pre_tokenizer = pre_tokenizers.Sequence([
pre_tokenizers.Split(
Regex(
r"""'s|'t|'re|'ve|'m|'ll|'d|[\p{L}]+|[\p{N}]|[^\s\p{L}\p{N}]+"""
),
behavior="removed",
invert=True,
),
pre_tokenizers.ByteLevel(add_prefix_space=False),
])
tokenizer.decoder = decoders.ByteLevel()
# Hack to have a ByteLevel and TemplaceProcessor
tokenizer.post_processor = processors.RobertaProcessing(
sep=(self.original_tokenizer.eos_token,
self.original_tokenizer.eos_token_id),
cls=(self.original_tokenizer.bos_token,
self.original_tokenizer.bos_token_id),
add_prefix_space=False,
trim_offsets=False,
)
return tokenizer
def train_tokenizer(sentences: List[str], serialize_path: str = "", vocab_size: int = 8000) -> Tokenizer:
bert_tokenizer = Tokenizer(WordPiece(unk_token="[UNK]"))
bert_tokenizer.normalizer = normalizers.Sequence([NFD(), Lowercase(), StripAccents()])
bert_tokenizer.pre_tokenizer = Whitespace()
bert_tokenizer.post_processor = TemplateProcessing(
single="[CLS] $A [SEP]",
pair="[CLS] $A [SEP] $B:1 [SEP]:1",
special_tokens=[
("[CLS]", 1),
("[SEP]", 2),
],
)
trainer = WordPieceTrainer(
vocab_size=vocab_size,
special_tokens=["[UNK]", "[CLS]", "[SEP]", "[PAD]", "[MASK]"]
)
bert_tokenizer.train_from_iterator(sentences, trainer=trainer)
if serialize_path:
bert_tokenizer.save(serialize_path)
return bert_tokenizer
def train_wordpiece_bert():
"""
Sample code from: https://huggingface.co/docs/tokenizers/python/latest/pipeline.html
"""
from tokenizers.models import WordPiece
bert_tokenizer = Tokenizer(WordPiece(unk_token="[UNK]"))
from tokenizers import normalizers
from tokenizers.normalizers import Lowercase, NFD, StripAccents
bert_tokenizer.normalizer = normalizers.Sequence(
[NFD(), Lowercase(), StripAccents()])
from tokenizers.pre_tokenizers import Whitespace
bert_tokenizer.pre_tokenizer = Whitespace()
from tokenizers.processors import TemplateProcessing
bert_tokenizer.post_processor = TemplateProcessing(
single="[CLS] $A [SEP]",
pair="[CLS] $A [SEP] $B:1 [SEP]:1",
special_tokens=[
("[CLS]", 1),
("[SEP]", 2),
],
)
bert_tokenizer.decoder = decoders.WordPiece()
from tokenizers.trainers import WordPieceTrainer
trainer = WordPieceTrainer(
vocab_size=30522,
special_tokens=["[UNK]", "[CLS]", "[SEP]", "[PAD]", "[MASK]"])
files = [
DIR_DATA + os.sep + 'wikitext-103' + os.sep + 'wiki.%s.raw' % a
for a in ["test", "train", "valid"]
]
bert_tokenizer.train(files, trainer)
bert_tokenizer.save(DIR_TOKENIZERS + os.sep + 'bert_wiki.json')
return bert_tokenizer
def train_tokenizer() -> tokenizers.Tokenizer:
tokenizer = tokenizers.Tokenizer(models.WordPiece(unk_token="<unk>"))
tokenizer.decoder = decoders.WordPiece()
tokenizer.normalizer = normalizers.Sequence([
normalizers.NFD(), # NFD unicode normalizer
normalizers.Lowercase(),
normalizers.StripAccents()
])
tokenizer.pre_tokenizer = tokenizers.pre_tokenizers.Sequence([
pre_tokenizers.Whitespace(),
pre_tokenizers.Digits(individual_digits=False)
])
tokenizer.post_processor = processors.TemplateProcessing(
single="$A </s>",
pair="$A </s> [SEP] <s> $B:1",
special_tokens=[("[SEP]", 1), ("<s>", 2), ("</s>", 3)])
# dataset = datasets.load_dataset("wikitext", "wikitext-103-raw-v1", split="train+test+validation")
dataset = datasets.load_dataset("wikitext",
"wikitext-103-raw-v1",
split="validation")
def batch_iterator(batch_size=1000):
for i in range(0, len(dataset), batch_size):
yield dataset[i:i + batch_size]["text"]
tokenizer.train_from_iterator(
batch_iterator(),
trainer=trainers.WordPieceTrainer(
vocab_size=10000, special_tokens=["<unk>", "[SEP]", "<s>",
"</s>"]))
def generator():
for record in dataset:
if record['text'].strip() != '':
yield record['text']
return tokenizer, generator
def __init__(
self,
vocab: Optional[Union[str, Dict[str, int]]] = None,
unk_token: Union[str, AddedToken] = "[UNK]",
sep_token: Union[str, AddedToken] = "[SEP]",
cls_token: Union[str, AddedToken] = "[CLS]",
pad_token: Union[str, AddedToken] = "[PAD]",
mask_token: Union[str, AddedToken] = "[MASK]",
num_unused_tokens: int = 10,
mecab_dic_type: str = "unidic_lite",
wordpieces_prefix: str = "##",
) -> None:
super().__init__(
vocab=vocab,
unk_token=unk_token,
sep_token=sep_token,
cls_token=cls_token,
pad_token=pad_token,
mask_token=mask_token,
wordpieces_prefix=wordpieces_prefix,
)
self._tokenizer.add_special_tokens(
['<unused{}>'.format(i) for i in range(num_unused_tokens)])
self._tokenizer.normalizer = normalizers.Sequence(
[normalizers.NFKC(), normalizers.Strip()])
if mecab_dic_type in ("unidic_lite", "unidic", "ipadic"):
self._tokenizer.pre_tokenizer = pre_tokenizers.PreTokenizer.custom(
MeCabPreTokenizer(mecab_dic_type))
elif mecab_dic_type == "whitespace":
self._tokenizer.pre_tokenizer = pre_tokenizers.WhitespaceSplit()
else:
raise ValueError("Invalid pre_tokenizer_type is specified.")
parameters = {
"model": "BertWordPieceJapaneseTokenizer",
"mecab_dic_type": mecab_dic_type,
}
self._parameters.update(parameters)
def normalizer(self, proto):
precompiled_charsmap = proto.normalizer_spec.precompiled_charsmap
return normalizers.Sequence([
normalizers.Precompiled(precompiled_charsmap),
normalizers.Replace(Regex(" {2,}"), " ")
])
def train_custom_tokenizer(dataset,
token_model,
tknzr_file,
vocab_size,
vocab=None,
pretrain_fast=False,
max_input_chars_per_word=None,
eos_token=None,
bos_token=None,
pad_token=None,
mask_token=None,
unk_token=None):
"""
Building a Tokenizer using HuggingFace library. The pipeline seems to be:
- Model : algorithm that tokenizes, it is a mandatory
component. There are only 4 models implemented
(BPE, Unigram, WordLevel, WordPiece)
- Normalizer : some preprocessing that could happen before, but
doesn't necessarily have to
- Pre-Tokenizer : splitting the input according to some rules
- Post-Processing : needing to add some tokens/input after (mostly seems
to be eos, bos tokens)
- Decoder : certain previous pipeline steps need to be reversed
for proper decoding
- Trainer : The corresponding training algorithm for the model
Note : Some pre-processing might need to happen beforehand in previous
functions (might be easier using pandas before)
Input
token_model (str) : algorithm to use for tokenization
dataset (class) : a python iterator that goes through the data
to be used for training
token_dir (str) : directory with tokenizers
vocab_size (int) : size of the vocabulary to use
tokenFilename (str) : filename of particular token we want to
train. Will overwrite previously save files.
vocab (list of str) : models other than BPE can use non-mandatory
vocab as input
max_input_chars_per_word : used for WordPiece
Output
tokenizer : huggingFace Tokenizer object, our fully
trainer tokenizer
"""
special_token_lst = [
pad_token, bos_token, eos_token, mask_token, unk_token
]
# NFKC
normalizer_lst = []
pre_tokenizer_lst = [Whitespace, ByteLevel]
decoder_lst = []
bos_idx = special_token_lst.index(bos_token)
eos_idx = special_token_lst.index(eos_token)
if token_model == 'BPE':
model = BPE(unk_token=unk_token)
Trainer = BpeTrainer
elif token_model == 'Unigram':
model = Unigram(vocab=vocab)
Trainer = UnigramTrainer
elif token_model == 'WordLevel':
model = WordLevel(unk_token=unk_token, vocab=vocab)
Trainer = WordLevelTrainer
elif token_model == 'WordPiece':
model = WordPiece(unk_token=unk_token,
vocab=vocab,
max_input_chars_per_word=max_input_chars_per_word)
Trainer = WordPieceTrainer
else:
error_msg = f'Error: token_model ({token_model}) not an algorithm in%s' \
% VALID_TOKENIZATIONS
raise SystemExit(error_msg)
# instantiation
tokenizer = Tokenizer(model)
# Select a tokenization trainer
if vocab_size is None:
trainer = Trainer(show_progress=True, special_tokens=special_token_lst)
else:
trainer = Trainer(vocab_size=vocab_size,
show_progress=True,
special_tokens=special_token_lst)
# Set the normalizer
tokenizer.normalizer = normalizers.Sequence(
[fcn() for fcn in normalizer_lst])
# Set the pre-tokenizer
tokenizer.pre_tokenizer = pre_tokenizers.Sequence(
[fcn() for fcn in pre_tokenizer_lst])
# Set the post-processing
tokenizer.post_processor = processors.TemplateProcessing(
single=bos_token + " $A " + eos_token,
special_tokens=[(bos_token, bos_idx), (eos_token, eos_idx)],
# pair=bos_token+" $A "+eos_token" $B:1 "+eos_token+":1",
)
# Set the decoder
if ByteLevel in pre_tokenizer_lst:
tokenizer.decoder = decoders.ByteLevel()
if Metaspace in pre_tokenizer_lst:
tokenizer.decoder = decoders.Metaspace()
if token_model == 'WordPiece':
tokenizer.decoder = decoders.WordPiece()
# creating iterator
def batch_iterator():
for i in np.arange(0, len(dataset)):
yield dataset[i]
# train call
tokenizer.train_from_iterator(trainer=trainer,
iterator=batch_iterator(),
length=len(dataset))
if Path(tknzr_file).exists():
print(f"Warning : overwriting previously save tokenizer with\
same filename ( {tknzr_file} ).")
tokenizer.save(tknzr_file)
if pretrain_fast:
tokenizer = PreTrainedTokenizerFast(tokenizer_file=tknzr_file)
else:
tokenizer = PreTrainedTokenizer(tokenizer_file=tknzr_file)
tokenizer.pad_token = pad_token
tokenizer.mask_token = mask_token
return tokenizer
import string, re
from tokenizers import normalizers
from tokenizers.normalizers import Lowercase, NFD, StripAccents, Strip, BertNormalizer
normalizer = normalizers.Sequence([BertNormalizer(), Strip()])
def delete_punct(w: str) -> str:
"""Delete all puctuation in a string."""
return w.lower().translate(
str.maketrans(string.punctuation,
len(string.punctuation) * " "))
def normalize(x):
y = normalizer.normalize_str(delete_punct(x))
y = y.replace("\n", " ")
# remove double spaces
y = re.sub(' +', ' ', y).strip()
return y
def get_str(x):
res = ''
if isinstance(x, dict):
for f in x:
if f not in ['lang']:
res += ' ' + get_str(x[f])
if isinstance(x, str):
res = x.strip()
if isinstance(x, list):
