Source code for mindnlp.transforms.tokenizers.t5_tokenizer

# Copyright 2023 Huawei Technologies Co., Ltd
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# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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#
# http://www.apache.org/licenses/LICENSE-2.0
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# Unless required by applicable law or agreed to in writing, software
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"""
T5Tokenizer
"""

import numpy as np
from mindspore.dataset.text.transforms import Implementation
from tokenizers import Tokenizer
from mindnlp.abc import PreTrainedTokenizer
from mindnlp.models.t5.t5_config import T5_SUPPORT_LIST
from mindnlp.configs import HF_TOKENIZER_CONFIG_URL_BASE

PRETRAINED_VOCAB_MAP = {
    model: HF_TOKENIZER_CONFIG_URL_BASE.format(model) for model in T5_SUPPORT_LIST
}

PRETRAINED_POSITIONAL_EMBEDDINGS_SIZES = {
    "t5-small": 512,
    "t5-base": 512,
    "t5-large": 512,
    "t5-3b": 512,
    "t5-11b": 512,
}

[docs]class T5Tokenizer(PreTrainedTokenizer): """ Tokenizer used for T5 text process. Args: vocab (Vocab): Vocabulary used to look up words. return_token (bool): Whether to return token. If True: return tokens. False: return ids. Default: True. Examples: >>> from mindspore.dataset import text >>> from mindnlp.transforms import T5Tokenizer >>> text = "Believing that faith can triumph over everything is in itself the greatest belief" >>> tokenizer = T5Tokenizer.from_pretrained('t5-base') >>> tokens = tokenizer.encode(text) """ max_model_input_sizes = PRETRAINED_POSITIONAL_EMBEDDINGS_SIZES pretrained_vocab_map = PRETRAINED_VOCAB_MAP def __init__(self, vocab: str, **kwargs): super().__init__() return_token = kwargs.pop('return_token', False) if isinstance(vocab, str): self.tokenizer = Tokenizer.from_file(vocab) else: raise ValueError(f'only support string, but got {vocab}') self.return_token = return_token self.implementation = Implementation.PY def __call__(self, text_input): """ Call method for input conversion for eager mode with C++ implementation. """ if isinstance(text_input, str): text_input = np.array(text_input) elif not isinstance(text_input, np.ndarray): raise TypeError( f"Input should be a text line in 1-D NumPy format, got {type(text_input)}.") return super().__call__(text_input)
[docs] def execute_py(self, text_input): """ Execute method. """ return self._execute_py(text_input)
def _execute_py(self, text_input): """ Execute method. """ text_input = self._convert_to_unicode(text_input) tokens = self.tokenizer.encode(text_input) if self.return_token is True: return np.array(tokens.tokens) return np.array(tokens.ids) def _convert_to_unicode(self, text_input): """Converts `text` to Unicode (if it's not already), assuming utf-8 input.""" if isinstance(text_input, str): return text_input if isinstance(text_input, bytes): return text_input.decode("utf-8", "ignore") if isinstance(text_input, np.ndarray): if text_input.dtype.type is np.bytes_: text_input = np.char.decode(text_input, "utf-8") return str(text_input) raise ValueError(f"Unsupported string type: {type(text_input)}, {text_input.dtype}")