* Added is_fast property on BatchEncoding to indicate if the object comes from a Fast Tokenizer. * Added __get_state__() & __set_state__() to be pickable. * Correct tokens() return type from List[int] to List[str] * Added unittest for BatchEncoding pickle/unpickle * Added unittest for BatchEncoding is_fast * More careful checking on BatchEncoding unpickle tests. * Formatting. * is_fast should assertTrue on Rust tokenizers. * Ensure tensorflow has correct way of checking array_equal * More formatting.
1794 lines
82 KiB
Python
1794 lines
82 KiB
Python
# coding=utf-8
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# Copyright 2020 The HuggingFace Inc. team.
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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""" Base classes common to both the slow and the fast tokenization classes:
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PreTrainedTokenizerBase (host all the user fronting encoding methodes)
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Special token mixing (host the special tokens logic) and
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BatchEncoding (wrap the dictionnary of output with special method for the Fast tokenizers)
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"""
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import copy
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import json
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import logging
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import os
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import warnings
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from collections import UserDict
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from enum import Enum
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from typing import Any, Dict, List, NamedTuple, Optional, Sequence, Tuple, Union
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import numpy as np
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from tokenizers import AddedToken as AddedTokenFast
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from tokenizers import Encoding as EncodingFast
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from .file_utils import (
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add_end_docstrings,
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cached_path,
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hf_bucket_url,
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is_remote_url,
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is_tf_available,
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is_torch_available,
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torch_required,
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)
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if is_tf_available():
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import tensorflow as tf
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if is_torch_available():
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import torch
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logger = logging.getLogger(__name__)
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VERY_LARGE_INTEGER = int(1e30) # This is used to set the max input length for a model with infinite size input
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LARGE_INTEGER = int(1e20) # This is used when we need something big but slightly smaller than VERY_LARGE_INTEGER
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# Define type aliases and NamedTuples
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TextInput = str
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PreTokenizedInput = List[str]
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EncodedInput = List[int]
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TextInputPair = Tuple[str, str]
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PreTokenizedInputPair = Tuple[List[str], List[str]]
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EncodedInputPair = Tuple[List[int], List[int]]
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SPECIAL_TOKENS_MAP_FILE = "special_tokens_map.json"
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ADDED_TOKENS_FILE = "added_tokens.json"
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TOKENIZER_CONFIG_FILE = "tokenizer_config.json"
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FULL_TOKENIZER_FILE = "tokenizer.json"
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class ExplicitEnum(Enum):
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""" Enum with more explicit error message for missing values.
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"""
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@classmethod
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def _missing_(cls, value):
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raise ValueError(
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"%r is not a valid %s, please select one of %s"
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% (value, cls.__name__, str(list(cls._value2member_map_.keys())))
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)
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class TruncationStrategy(ExplicitEnum):
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ONLY_FIRST = "only_first"
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ONLY_SECOND = "only_second"
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LONGEST_FIRST = "longest_first"
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DO_NOT_TRUNCATE = "do_not_truncate"
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class PaddingStrategy(ExplicitEnum):
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LONGEST = "longest"
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MAX_LENGTH = "max_length"
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DO_NOT_PAD = "do_not_pad"
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class TensorType(ExplicitEnum):
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PYTORCH = "pt"
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TENSORFLOW = "tf"
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NUMPY = "np"
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class CharSpan(NamedTuple):
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""" Character span in the original string
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Args:
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start: index of the first character in the original string
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end: index of the character following the last character in the original string
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"""
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start: int
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end: int
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class TokenSpan(NamedTuple):
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""" Token span in an encoded string (list of tokens)
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Args:
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start: index of the first token in the span
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end: index of the token following the last token in the span
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"""
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start: int
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end: int
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class BatchEncoding(UserDict):
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""" BatchEncoding hold the output of the encode and batch_encode methods (tokens, attention_masks, etc).
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This class is derived from a python Dictionary and can be used as a dictionnary.
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In addition, this class expose utility methods to map from word/char space to token space.
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Args:
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data (:obj:`dict`): Dictionary of lists/arrays returned by the encode/batch_encode methods ('input_ids', 'attention_mask'...)
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encoding (:obj:`EncodingFast`, :obj:`list(EncodingFast)`, `optional`, defaults to :obj:`None`):
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If the tokenizer is a fast tokenizer which outputs additional informations like mapping from word/char space to token space
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the `EncodingFast` instance or list of instance (for batches) hold these informations.
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tensor_type (:obj:`Union[None, str, TensorType]`, `optional`, defaults to :obj:`None`):
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You can give a tensor_type here to convert the lists of integers in PyTorch/TF/Numpy Tensors at initialization
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prepend_batch_axis (:obj:`bool`, `optional`, defaults to :obj:`False`):
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Set to True to add a batch axis when converting in Tensors (see :obj:`tensor_type` above)
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"""
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def __init__(
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self,
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data: Optional[Dict[str, Any]] = None,
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encoding: Optional[Union[EncodingFast, Sequence[EncodingFast]]] = None,
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tensor_type: Union[None, str, TensorType] = None,
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prepend_batch_axis: bool = False,
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):
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super().__init__(data)
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if isinstance(encoding, EncodingFast):
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encoding = [encoding]
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self._encodings = encoding
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self.convert_to_tensors(tensor_type=tensor_type, prepend_batch_axis=prepend_batch_axis)
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@property
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def is_fast(self):
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"""
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Indicate if this BatchEncoding was generated from the result of a PreTrainedTokenizerFast
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Returns: True if generated from subclasses of PreTrainedTokenizerFast, else otherwise
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"""
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return self._encodings is not None
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def __getitem__(self, item: Union[int, str]) -> EncodingFast:
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""" If the key is a string, get the value of the dict associated to `key` ('input_ids', 'attention_mask'...)
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If the key is an integer, get the EncodingFast for batch item with index `key`
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"""
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if isinstance(item, str):
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return self.data[item]
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elif self._encodings is not None:
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return self._encodings[item]
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else:
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raise KeyError(
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"Indexing with integers (to access backend Encoding for a given batch index) "
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"is not available when using Python based tokenizers"
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)
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def __getattr__(self, item: str):
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try:
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return self.data[item]
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except KeyError:
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raise AttributeError
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def __getstate__(self):
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return {"data": self.data, "encodings": self._encodings}
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def __setstate__(self, state):
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if "data" in state:
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self.data = state["data"]
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if "encodings" in state:
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self._encodings = state["encodings"]
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def keys(self):
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return self.data.keys()
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def values(self):
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return self.data.values()
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def items(self):
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return self.data.items()
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# After this point:
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# Extended properties and methods only available for fast (Rust-based) tokenizers
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# provided by HuggingFace tokenizers library.
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@property
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def encodings(self) -> Optional[List[EncodingFast]]:
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"""
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Return the list all encoding from the tokenization process
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Returns: List[EncodingFast] or None if input was tokenized through Python (i.e. not fast) tokenizer
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"""
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return self._encodings
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def tokens(self, batch_index: int = 0) -> List[str]:
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if not self._encodings:
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raise ValueError("tokens() is not available when using Python based tokenizers")
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return self._encodings[batch_index].tokens
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def words(self, batch_index: int = 0) -> List[Optional[int]]:
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if not self._encodings:
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raise ValueError("words() is not available when using Python based tokenizers")
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return self._encodings[batch_index].words
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def token_to_word(self, batch_or_token_index: int, token_index: Optional[int] = None) -> int:
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"""
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Get the index of the word corresponding (i.e. comprising) to an encoded token
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in a sequence of the batch.
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Can be called as:
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- ``self.token_to_word(token_index)`` if batch size is 1
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- ``self.token_to_word(batch_index, token_index)`` if batch size is greater than 1
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This method is particularly suited when the input sequences are provided as
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pre-tokenized sequences (i.e. words are defined by the user). In this case it allows
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to easily associate encoded tokens with provided tokenized words.
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Args:
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batch_or_token_index (:obj:`int`):
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Index of the sequence in the batch. If the batch only comprise one sequence,
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this can be the index of the token in the sequence
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token_index (:obj:`int`, `optional`):
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If a batch index is provided in `batch_or_token_index`, this can be the index
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of the token in the sequence.
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Returns:
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:obj:`int`:
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index of the word in the input sequence.
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"""
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if not self._encodings:
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raise ValueError("token_to_word() is not available when using Python based tokenizers")
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if token_index is not None:
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batch_index = batch_or_token_index
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else:
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batch_index = 0
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token_index = batch_or_token_index
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if batch_index < 0:
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batch_index = self._batch_size + batch_index
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if token_index < 0:
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token_index = self._seq_len + token_index
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return self._encodings[batch_index].token_to_word(token_index)
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def word_to_tokens(self, batch_or_word_index: int, word_index: Optional[int] = None) -> TokenSpan:
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"""
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Get the encoded token span corresponding to a word in the sequence of the batch.
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Token spans are returned as a TokenSpan NamedTuple with:
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- start: index of the first token
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- end: index of the token following the last token
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Can be called as:
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- ``self.word_to_tokens(word_index)`` if batch size is 1
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- ``self.word_to_tokens(batch_index, word_index)`` if batch size is greater or equal to 1
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This method is particularly suited when the input sequences are provided as
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pre-tokenized sequences (i.e. words are defined by the user). In this case it allows
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to easily associate encoded tokens with provided tokenized words.
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Args:
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batch_or_word_index (:obj:`int`):
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Index of the sequence in the batch. If the batch only comprises one sequence,
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this can be the index of the word in the sequence
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word_index (:obj:`int`, `optional`):
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If a batch index is provided in `batch_or_token_index`, this can be the index
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of the word in the sequence.
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Returns:
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:obj:`TokenSpan`:
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Span of tokens in the encoded sequence.
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:obj:`TokenSpan` are NamedTuple with:
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- start: index of the first token
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- end: index of the token following the last token
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"""
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if not self._encodings:
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raise ValueError("word_to_tokens() is not available when using Python based tokenizers")
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if word_index is not None:
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batch_index = batch_or_word_index
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else:
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batch_index = 0
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word_index = batch_or_word_index
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if batch_index < 0:
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batch_index = self._batch_size + batch_index
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if word_index < 0:
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word_index = self._seq_len + word_index
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return TokenSpan(*(self._encodings[batch_index].word_to_tokens(word_index)))
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def token_to_chars(self, batch_or_token_index: int, token_index: Optional[int] = None) -> CharSpan:
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"""
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Get the character span corresponding to an encoded token in a sequence of the batch.
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Character spans are returned as a CharSpan NamedTuple with:
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- start: index of the first character in the original string associated to the token
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- end: index of the character following the last character in the original string associated to the token
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Can be called as:
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- ``self.token_to_chars(token_index)`` if batch size is 1
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- ``self.token_to_chars(batch_index, token_index)`` if batch size is greater or equal to 1
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Args:
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batch_or_token_index (:obj:`int`):
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Index of the sequence in the batch. If the batch only comprise one sequence,
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this can be the index of the token in the sequence
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token_index (:obj:`int`, `optional`):
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If a batch index is provided in `batch_or_token_index`, this can be the index
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of the token or tokens in the sequence.
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Returns:
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:obj:`CharSpan`:
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Span of characters in the original string.
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:obj:`CharSpan` are NamedTuple with:
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- start: index of the first character in the original string
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- end: index of the character following the last character in the original string
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"""
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if not self._encodings:
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raise ValueError("token_to_chars() is not available when using Python based tokenizers")
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if token_index is not None:
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batch_index = batch_or_token_index
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else:
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batch_index = 0
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token_index = batch_or_token_index
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return CharSpan(*(self._encodings[batch_index].token_to_chars(token_index)))
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def char_to_token(self, batch_or_char_index: int, char_index: Optional[int] = None) -> int:
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"""
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Get the index of the token in the encoded output comprising a character
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in the original string for a sequence of the batch.
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Can be called as:
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- ``self.char_to_token(char_index)`` if batch size is 1
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- ``self.char_to_token(batch_index, char_index)`` if batch size is greater or equal to 1
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|
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|
This method is particularly suited when the input sequences are provided as
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pre-tokenized sequences (i.e. words are defined by the user). In this case it allows
|
|
to easily associate encoded tokens with provided tokenized words.
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|
|
|
Args:
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batch_or_char_index (:obj:`int`):
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|
Index of the sequence in the batch. If the batch only comprise one sequence,
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this can be the index of the word in the sequence
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char_index (:obj:`int`, `optional`):
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If a batch index is provided in `batch_or_token_index`, this can be the index
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of the word in the sequence.
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Returns:
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:obj:`int`: Index of the token.
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"""
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if not self._encodings:
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raise ValueError("char_to_token() is not available when using Python based tokenizers")
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if char_index is not None:
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batch_index = batch_or_char_index
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else:
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batch_index = 0
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char_index = batch_or_char_index
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return self._encodings[batch_index].char_to_token(char_index)
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def word_to_chars(self, batch_or_word_index: int, word_index: Optional[int] = None) -> CharSpan:
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"""
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|
Get the character span in the original string corresponding to given word in a sequence
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of the batch.
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|
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|
Character spans are returned as a CharSpan NamedTuple with:
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|
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|
- start: index of the first character in the original string
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|
- end: index of the character following the last character in the original string
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|
|
|
Can be called as:
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|
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|
- ``self.word_to_chars(word_index)`` if batch size is 1
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- ``self.word_to_chars(batch_index, word_index)`` if batch size is greater or equal to 1
|
|
|
|
Args:
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|
batch_or_word_index (:obj:`int`):
|
|
Index of the sequence in the batch. If the batch only comprise one sequence,
|
|
this can be the index of the word in the sequence
|
|
word_index (:obj:`int`, `optional`):
|
|
If a batch index is provided in `batch_or_token_index`, this can be the index
|
|
of the word in the sequence.
|
|
|
|
Returns:
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|
:obj:`CharSpan` or :obj:`List[CharSpan]`:
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|
Span(s) of the associated character or characters in the string.
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|
CharSpan are NamedTuple with:
|
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|
- start: index of the first character associated to the token in the original string
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- end: index of the character following the last character associated to the token in the original string
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"""
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|
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|
if not self._encodings:
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raise ValueError("word_to_chars() is not available when using Python based tokenizers")
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|
if word_index is not None:
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batch_index = batch_or_word_index
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else:
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batch_index = 0
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word_index = batch_or_word_index
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return CharSpan(*(self._encodings[batch_index].word_to_chars(word_index)))
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|
|
|
def char_to_word(self, batch_or_char_index: int, char_index: Optional[int] = None) -> int:
|
|
"""
|
|
Get the word in the original string corresponding to a character in the original string of
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|
a sequence of the batch.
|
|
|
|
Can be called as:
|
|
|
|
- ``self.char_to_word(char_index)`` if batch size is 1
|
|
- ``self.char_to_word(batch_index, char_index)`` if batch size is greater than 1
|
|
|
|
This method is particularly suited when the input sequences are provided as
|
|
pre-tokenized sequences (i.e. words are defined by the user). In this case it allows
|
|
to easily associate encoded tokens with provided tokenized words.
|
|
|
|
Args:
|
|
batch_or_char_index (:obj:`int`):
|
|
Index of the sequence in the batch. If the batch only comprise one sequence,
|
|
this can be the index of the character in the orginal string.
|
|
char_index (:obj:`int`, `optional`):
|
|
If a batch index is provided in `batch_or_token_index`, this can be the index
|
|
of the character in the orginal string.
|
|
|
|
|
|
Returns:
|
|
:obj:`int` or :obj:`List[int]`:
|
|
Index or indices of the associated encoded token(s).
|
|
"""
|
|
|
|
if not self._encodings:
|
|
raise ValueError("char_to_word() is not available when using Python based tokenizers")
|
|
if char_index is not None:
|
|
batch_index = batch_or_char_index
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|
else:
|
|
batch_index = 0
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char_index = batch_or_char_index
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return self._encodings[batch_index].char_to_word(char_index)
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|
|
|
def convert_to_tensors(self, tensor_type: Union[None, str, TensorType], prepend_batch_axis: bool = False):
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|
if tensor_type is None:
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return self
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|
|
|
# Convert to TensorType
|
|
if not isinstance(tensor_type, TensorType):
|
|
tensor_type = TensorType(tensor_type)
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|
|
|
# Get a function reference for the correct framework
|
|
if tensor_type == TensorType.TENSORFLOW and is_tf_available():
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as_tensor = tf.constant
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|
elif tensor_type == TensorType.PYTORCH and is_torch_available():
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|
as_tensor = torch.tensor
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|
elif tensor_type == TensorType.NUMPY:
|
|
as_tensor = np.asarray
|
|
else:
|
|
raise ImportError(
|
|
"Unable to convert output to tensors format {}, PyTorch or TensorFlow is not available.".format(
|
|
tensor_type
|
|
)
|
|
)
|
|
|
|
# Do the tensor conversion in batch
|
|
for key, value in self.items():
|
|
try:
|
|
if prepend_batch_axis:
|
|
value = [value]
|
|
|
|
tensor = as_tensor(value)
|
|
|
|
# at-least2d
|
|
if tensor.ndim > 2:
|
|
tensor = tensor.squeeze(0)
|
|
elif tensor.ndim < 2:
|
|
tensor = tensor[None, :]
|
|
|
|
self[key] = tensor
|
|
except: # noqa E722
|
|
raise ValueError(
|
|
"Unable to create tensor, you should probably activate truncation and/or padding "
|
|
"with 'padding=True' 'truncation=True' to have batched tensors with the same length."
|
|
)
|
|
|
|
return self
|
|
|
|
@torch_required
|
|
def to(self, device: str):
|
|
"""Send all values to device by calling v.to(device)"""
|
|
self.data = {k: v.to(device) for k, v in self.data.items()}
|
|
return self
|
|
|
|
|
|
class SpecialTokensMixin:
|
|
""" SpecialTokensMixin is derived by ``PreTrainedTokenizer`` and ``PreTrainedTokenizerFast`` and
|
|
handles specific behaviors related to special tokens. In particular, this class hold the
|
|
attributes which can be used to directly access to these special tokens in a
|
|
model-independant manner and allow to set and update the special tokens.
|
|
"""
|
|
|
|
SPECIAL_TOKENS_ATTRIBUTES = [
|
|
"bos_token",
|
|
"eos_token",
|
|
"unk_token",
|
|
"sep_token",
|
|
"pad_token",
|
|
"cls_token",
|
|
"mask_token",
|
|
"additional_special_tokens",
|
|
]
|
|
|
|
def __init__(self, verbose=True, **kwargs):
|
|
self._bos_token = None
|
|
self._eos_token = None
|
|
self._unk_token = None
|
|
self._sep_token = None
|
|
self._pad_token = None
|
|
self._cls_token = None
|
|
self._mask_token = None
|
|
self._pad_token_type_id = 0
|
|
self._additional_special_tokens = []
|
|
self.verbose = verbose
|
|
|
|
for key, value in kwargs.items():
|
|
if key in self.SPECIAL_TOKENS_ATTRIBUTES:
|
|
if key == "additional_special_tokens":
|
|
assert isinstance(value, (list, tuple)) and all(isinstance(t, str) for t in value)
|
|
elif isinstance(value, AddedTokenFast):
|
|
setattr(self, key, str(value))
|
|
elif isinstance(value, str):
|
|
setattr(self, key, value)
|
|
else:
|
|
raise TypeError(
|
|
"special token {} has to be either str or AddedTokenFast but got: {}".format(key, type(value))
|
|
)
|
|
|
|
def add_special_tokens(self, special_tokens_dict):
|
|
"""
|
|
Add a dictionary of special tokens (eos, pad, cls...) to the encoder and link them
|
|
to class attributes. If special tokens are NOT in the vocabulary, they are added
|
|
to it (indexed starting from the last index of the current vocabulary).
|
|
|
|
Using `add_special_tokens` will ensure your special tokens can be used in several ways:
|
|
|
|
- special tokens are carefully handled by the tokenizer (they are never split)
|
|
- you can easily refer to special tokens using tokenizer class attributes like `tokenizer.cls_token`. This makes it easy to develop model-agnostic training and fine-tuning scripts.
|
|
|
|
When possible, special tokens are already registered for provided pretrained models (ex: BertTokenizer cls_token is already registered to be '[CLS]' and XLM's one is also registered to be '</s>')
|
|
|
|
Args:
|
|
special_tokens_dict: dict of string. Keys should be in the list of predefined special attributes:
|
|
[``bos_token``, ``eos_token``, ``unk_token``, ``sep_token``, ``pad_token``, ``cls_token``, ``mask_token``,
|
|
``additional_special_tokens``].
|
|
|
|
Tokens are only added if they are not already in the vocabulary (tested by checking if the tokenizer assign the index of the ``unk_token`` to them).
|
|
|
|
Returns:
|
|
Number of tokens added to the vocabulary.
|
|
|
|
Examples::
|
|
|
|
# Let's see how to add a new classification token to GPT-2
|
|
tokenizer = GPT2Tokenizer.from_pretrained('gpt2')
|
|
model = GPT2Model.from_pretrained('gpt2')
|
|
|
|
special_tokens_dict = {'cls_token': '<CLS>'}
|
|
|
|
num_added_toks = tokenizer.add_special_tokens(special_tokens_dict)
|
|
print('We have added', num_added_toks, 'tokens')
|
|
model.resize_token_embeddings(len(tokenizer)) # Notice: resize_token_embeddings expect to receive the full size of the new vocabulary, i.e. the length of the tokenizer.
|
|
|
|
assert tokenizer.cls_token == '<CLS>'
|
|
"""
|
|
if not special_tokens_dict:
|
|
return 0
|
|
|
|
added_tokens = 0
|
|
for key, value in special_tokens_dict.items():
|
|
assert key in self.SPECIAL_TOKENS_ATTRIBUTES
|
|
if key == "additional_special_tokens":
|
|
assert isinstance(value, (list, tuple)) and all(isinstance(t, str) for t in value)
|
|
added_tokens += self.add_tokens(value)
|
|
else:
|
|
assert isinstance(value, str)
|
|
added_tokens += self.add_tokens([value])
|
|
if self.verbose:
|
|
logger.info("Assigning %s to the %s key of the tokenizer", value, key)
|
|
setattr(self, key, value)
|
|
|
|
return added_tokens
|
|
|
|
def add_tokens(self, value):
|
|
""" To be overriden by derived class to add a token in the vocabulary. """
|
|
pass
|
|
|
|
def _maybe_update_backend(self, value):
|
|
""" To be overriden by derived class if a backend tokenizer has to be updated. """
|
|
pass
|
|
|
|
@property
|
|
def bos_token(self):
|
|
""" Beginning of sentence token (string). Log an error if used while not having been set. """
|
|
if self._bos_token is None and self.verbose:
|
|
logger.error("Using bos_token, but it is not set yet.")
|
|
return self._bos_token
|
|
|
|
@property
|
|
def eos_token(self):
|
|
""" End of sentence token (string). Log an error if used while not having been set. """
|
|
if self._eos_token is None and self.verbose:
|
|
logger.error("Using eos_token, but it is not set yet.")
|
|
return self._eos_token
|
|
|
|
@property
|
|
def unk_token(self):
|
|
""" Unknown token (string). Log an error if used while not having been set. """
|
|
if self._unk_token is None and self.verbose:
|
|
logger.error("Using unk_token, but it is not set yet.")
|
|
return self._unk_token
|
|
|
|
@property
|
|
def sep_token(self):
|
|
""" Separation token (string). E.g. separate context and query in an input sequence. Log an error if used while not having been set. """
|
|
if self._sep_token is None and self.verbose:
|
|
logger.error("Using sep_token, but it is not set yet.")
|
|
return self._sep_token
|
|
|
|
@property
|
|
def pad_token(self):
|
|
""" Padding token (string). Log an error if used while not having been set. """
|
|
if self._pad_token is None and self.verbose:
|
|
logger.error("Using pad_token, but it is not set yet.")
|
|
return self._pad_token
|
|
|
|
@property
|
|
def cls_token(self):
|
|
""" Classification token (string). E.g. to extract a summary of an input sequence leveraging self-attention along the full depth of the model. Log an error if used while not having been set. """
|
|
if self._cls_token is None and self.verbose:
|
|
logger.error("Using cls_token, but it is not set yet.")
|
|
return self._cls_token
|
|
|
|
@property
|
|
def mask_token(self):
|
|
""" Mask token (string). E.g. when training a model with masked-language modeling. Log an error if used while not having been set. """
|
|
if self._mask_token is None and self.verbose:
|
|
logger.error("Using mask_token, but it is not set yet.")
|
|
return self._mask_token
|
|
|
|
@property
|
|
def additional_special_tokens(self):
|
|
""" All the additional special tokens you may want to use (list of strings). Log an error if used while not having been set. """
|
|
if self._additional_special_tokens is None and self.verbose:
|
|
logger.error("Using additional_special_tokens, but it is not set yet.")
|
|
return self._additional_special_tokens
|
|
|
|
@bos_token.setter
|
|
def bos_token(self, value):
|
|
self._bos_token = value
|
|
self._maybe_update_backend([value])
|
|
|
|
@eos_token.setter
|
|
def eos_token(self, value):
|
|
self._eos_token = value
|
|
self._maybe_update_backend([value])
|
|
|
|
@unk_token.setter
|
|
def unk_token(self, value):
|
|
self._unk_token = value
|
|
self._maybe_update_backend([value])
|
|
|
|
@sep_token.setter
|
|
def sep_token(self, value):
|
|
self._sep_token = value
|
|
self._maybe_update_backend([value])
|
|
|
|
@pad_token.setter
|
|
def pad_token(self, value):
|
|
self._pad_token = value
|
|
self._maybe_update_backend([value])
|
|
|
|
@cls_token.setter
|
|
def cls_token(self, value):
|
|
self._cls_token = value
|
|
self._maybe_update_backend([value])
|
|
|
|
@mask_token.setter
|
|
def mask_token(self, value):
|
|
self._mask_token = value
|
|
self._maybe_update_backend([value])
|
|
|
|
@additional_special_tokens.setter
|
|
def additional_special_tokens(self, value):
|
|
self._additional_special_tokens = value
|
|
self._maybe_update_backend(value)
|
|
|
|
@property
|
|
def bos_token_id(self):
|
|
""" Id of the beginning of sentence token in the vocabulary. Log an error if used while not having been set. """
|
|
return self.convert_tokens_to_ids(self.bos_token)
|
|
|
|
@property
|
|
def eos_token_id(self):
|
|
""" Id of the end of sentence token in the vocabulary. Log an error if used while not having been set. """
|
|
return self.convert_tokens_to_ids(self.eos_token)
|
|
|
|
@property
|
|
def unk_token_id(self):
|
|
""" Id of the unknown token in the vocabulary. Log an error if used while not having been set. """
|
|
return self.convert_tokens_to_ids(self.unk_token)
|
|
|
|
@property
|
|
def sep_token_id(self):
|
|
""" Id of the separation token in the vocabulary. E.g. separate context and query in an input sequence. Log an error if used while not having been set. """
|
|
return self.convert_tokens_to_ids(self.sep_token)
|
|
|
|
@property
|
|
def pad_token_id(self):
|
|
""" Id of the padding token in the vocabulary. Log an error if used while not having been set. """
|
|
return self.convert_tokens_to_ids(self.pad_token)
|
|
|
|
@property
|
|
def pad_token_type_id(self):
|
|
""" Id of the padding token type in the vocabulary."""
|
|
return self._pad_token_type_id
|
|
|
|
@property
|
|
def cls_token_id(self):
|
|
""" Id of the classification token in the vocabulary. E.g. to extract a summary of an input sequence leveraging self-attention along the full depth of the model. Log an error if used while not having been set. """
|
|
return self.convert_tokens_to_ids(self.cls_token)
|
|
|
|
@property
|
|
def mask_token_id(self):
|
|
""" Id of the mask token in the vocabulary. E.g. when training a model with masked-language modeling. Log an error if used while not having been set. """
|
|
return self.convert_tokens_to_ids(self.mask_token)
|
|
|
|
@property
|
|
def additional_special_tokens_ids(self):
|
|
""" Ids of all the additional special tokens in the vocabulary (list of integers). Log an error if used while not having been set. """
|
|
return self.convert_tokens_to_ids(self.additional_special_tokens)
|
|
|
|
@property
|
|
def special_tokens_map(self):
|
|
""" A dictionary mapping special token class attribute (cls_token, unk_token...) to their
|
|
values ('<unk>', '<cls>'...)
|
|
"""
|
|
set_attr = {}
|
|
for attr in self.SPECIAL_TOKENS_ATTRIBUTES:
|
|
attr_value = getattr(self, "_" + attr)
|
|
if attr_value:
|
|
set_attr[attr] = attr_value
|
|
return set_attr
|
|
|
|
@property
|
|
def all_special_tokens(self):
|
|
""" List all the special tokens ('<unk>', '<cls>'...) mapped to class attributes
|
|
(cls_token, unk_token...).
|
|
"""
|
|
all_toks = []
|
|
set_attr = self.special_tokens_map
|
|
for attr_value in set_attr.values():
|
|
all_toks = all_toks + (list(attr_value) if isinstance(attr_value, (list, tuple)) else [attr_value])
|
|
all_toks = list(set(all_toks))
|
|
return all_toks
|
|
|
|
@property
|
|
def all_special_ids(self):
|
|
""" List the vocabulary indices of the special tokens ('<unk>', '<cls>'...) mapped to
|
|
class attributes (cls_token, unk_token...).
|
|
"""
|
|
all_toks = self.all_special_tokens
|
|
all_ids = self.convert_tokens_to_ids(all_toks)
|
|
return all_ids
|
|
|
|
|
|
ENCODE_KWARGS_DOCSTRING = r"""
|
|
add_special_tokens (:obj:`bool`, `optional`, defaults to :obj:`True`):
|
|
If set to ``True``, the sequences will be encoded with the special tokens relative
|
|
to their model.
|
|
`padding` (:obj:`Union[bool, str]`, `optional`, defaults to :obj:`False`):
|
|
Activate and control padding. Accepts the following values:
|
|
|
|
* `True` or `'longest'`: pad to the longest sequence in the batch (or no padding if only a single sequence if provided),
|
|
* `'max_length'`: pad to a max length specified in `max_length` or to the max acceptable input length for the model if no length is provided (`max_length=None`)
|
|
* `False` or `'do_not_pad'` (default): No padding (i.e. can output batch with sequences of uneven lengths)
|
|
`truncation` (:obj:`Union[bool, str]`, `optional`, defaults to :obj:`False`):
|
|
Activate and control truncation. Accepts the following values:
|
|
|
|
* `True` or `'only_first'`: truncate to a max length specified in `max_length` or to the max acceptable input length for the model if no length is provided (`max_length=None`). This will only truncate the first sequence of a pair if a pair of sequences (or a batch of pairs) is provided,
|
|
* `'only_second'`: truncate to a max length specified in `max_length` or to the max acceptable input length for the model if no length is provided (`max_length=None`). This will only truncate the second sequence of a pair if a pair of sequences (or a batch of pairs) is provided,
|
|
* `'longest_first'`: truncate to a max length specified in `max_length` or to the max acceptable input length for the model if no length is provided (`max_length=None`). This will truncate token by token, removing a token from the longest sequence in the pair if a pair of sequences (or a batch of pairs) is provided,
|
|
* `False` or `'do_not_truncate'` (default): No truncation (i.e. can output batch with sequences length greater than the model max admissible input size)
|
|
`max_length` (:obj:`Union[int, None]`, `optional`, defaults to :obj:`None`):
|
|
Control the length for padding/truncation. Accepts the following values
|
|
|
|
* `None` (default): This will use the predefined model max length if required by one of the truncation/padding parameters. If the model has no specific max input length (e.g. XLNet) truncation/padding to max length is deactivated.
|
|
* `any integer value` (e.g. `42`): Use this specific maximum length value if required by one of the truncation/padding parameters.
|
|
stride (:obj:`int`, `optional`, defaults to ``0``):
|
|
If set to a number along with max_length, the overflowing tokens returned when `return_overflowing_tokens=True`
|
|
will contain some tokens from the end of the truncated sequence returned to provide some overlap between truncated and overflow ing sequences.
|
|
The value of this argument defines the number of overlapping tokens.
|
|
is_pretokenized (:obj:`bool`, defaults to :obj:`False`):
|
|
Set to True to indicate the input is already tokenized
|
|
return_tensors (:obj:`str`, `optional`, defaults to :obj:`None`):
|
|
Can be set to 'tf', 'pt' or 'np' to return respectively TensorFlow :obj:`tf.constant`,
|
|
PyTorch :obj:`torch.Tensor` or Numpy :oj: `np.ndarray` instead of a list of python integers.
|
|
"""
|
|
|
|
ENCODE_PLUS_ADDITIONAL_KWARGS_DOCSTRING = r"""
|
|
return_token_type_ids (:obj:`bool`, `optional`, defaults to :obj:`None`):
|
|
Whether to return token type IDs. If left to the default, will return the token type IDs according
|
|
to the specific tokenizer's default, defined by the :obj:`return_outputs` attribute.
|
|
|
|
`What are token type IDs? <../glossary.html#token-type-ids>`_
|
|
return_attention_mask (:obj:`bool`, `optional`, defaults to :obj:`none`):
|
|
Whether to return the attention mask. If left to the default, will return the attention mask according
|
|
to the specific tokenizer's default, defined by the :obj:`return_outputs` attribute.
|
|
|
|
`What are attention masks? <../glossary.html#attention-mask>`__
|
|
return_overflowing_tokens (:obj:`bool`, `optional`, defaults to :obj:`False`):
|
|
Set to True to return overflowing token sequences (default False).
|
|
return_special_tokens_mask (:obj:`bool`, `optional`, defaults to :obj:`False`):
|
|
Set to True to return special tokens mask information (default False).
|
|
return_offsets_mapping (:obj:`bool`, `optional`, defaults to :obj:`False`):
|
|
Set to True to return (char_start, char_end) for each token (default False).
|
|
If using Python's tokenizer, this method will raise NotImplementedError.
|
|
This one is only available on fast tokenizers inheriting from PreTrainedTokenizerFast.
|
|
**kwargs: passed to the `self.tokenize()` method
|
|
|
|
Return:
|
|
A Dictionary of shape::
|
|
|
|
{
|
|
input_ids: list[int],
|
|
token_type_ids: list[int] if return_token_type_ids is True (default)
|
|
attention_mask: list[int] if return_attention_mask is True (default)
|
|
overflowing_tokens: list[int] if the tokenizer is a slow tokenize, else a List[List[int]] if a ``max_length`` is specified and ``return_overflowing_tokens=True``
|
|
special_tokens_mask: list[int] if ``add_special_tokens`` if set to ``True``
|
|
and return_special_tokens_mask is True
|
|
}
|
|
|
|
With the fields:
|
|
|
|
- ``input_ids``: list of token ids to be fed to a model
|
|
- ``token_type_ids``: list of token type ids to be fed to a model
|
|
- ``attention_mask``: list of indices specifying which tokens should be attended to by the model
|
|
- ``overflowing_tokens``: list of overflowing tokens sequences if a max length is specified and ``return_overflowing_tokens=True``.
|
|
- ``special_tokens_mask``: if adding special tokens, this is a list of [0, 1], with 0 specifying special added
|
|
tokens and 1 specifying sequence tokens.
|
|
"""
|
|
|
|
|
|
class PreTrainedTokenizerBase(SpecialTokensMixin):
|
|
""" Base class for slow and fast tokenizers.
|
|
|
|
Handle shared (mostly boiler plate) methods for slow and fast tokenizers.
|
|
"""
|
|
|
|
vocab_files_names: Dict[str, str] = {}
|
|
pretrained_vocab_files_map: Dict[str, Dict[str, str]] = {}
|
|
pretrained_init_configuration: Dict[str, Dict[str, Any]] = {}
|
|
max_model_input_sizes: Dict[str, int] = {}
|
|
model_input_names: List[str] = ["token_type_ids", "attention_mask"]
|
|
|
|
padding_side: str = "right"
|
|
|
|
def __init__(self, model_max_length=None, **kwargs):
|
|
super().__init__(**kwargs)
|
|
|
|
# For backward compatibility we fallback to set model_max_length from max_len if provided
|
|
model_max_length = model_max_length if model_max_length is not None else kwargs.pop("max_len", None)
|
|
self.model_max_length = model_max_length if model_max_length is not None else VERY_LARGE_INTEGER
|
|
|
|
# Padding side is right by default and overridden in subclasses. If specified in the kwargs, it is changed.
|
|
self.padding_side = kwargs.pop("padding_side", self.padding_side)
|
|
assert self.padding_side in [
|
|
"right",
|
|
"left",
|
|
], f"Padding side should be selected between 'right' and 'left', current value: {self.padding_side}"
|
|
self.model_input_names = kwargs.pop("model_input_names", self.model_input_names)
|
|
|
|
# inputs and kwargs for saving and re-loading (see ``from_pretrained`` and ``save_pretrained``)
|
|
self.init_inputs = ()
|
|
self.init_kwargs = {}
|
|
|
|
@property
|
|
def max_len(self) -> int:
|
|
""" Kept here for backward compatibility.
|
|
Now renamed to `model_max_length` to avoid ambiguity.
|
|
"""
|
|
return self.model_max_length
|
|
|
|
@property
|
|
def max_len_single_sentence(self) -> int:
|
|
return self.model_max_length - self.num_special_tokens_to_add(pair=False)
|
|
|
|
@property
|
|
def max_len_sentences_pair(self) -> int:
|
|
return self.model_max_length - self.num_special_tokens_to_add(pair=True)
|
|
|
|
@max_len_single_sentence.setter
|
|
def max_len_single_sentence(self, value) -> int:
|
|
""" For backward compatibility, allow to try to setup 'max_len_single_sentence' """
|
|
if value == self.model_max_length - self.num_special_tokens_to_add(pair=False) and self.verbose:
|
|
logger.warning(
|
|
"Setting 'max_len_single_sentence' is now deprecated. " "This value is automatically set up."
|
|
)
|
|
else:
|
|
raise ValueError(
|
|
"Setting 'max_len_single_sentence' is now deprecated. " "This value is automatically set up."
|
|
)
|
|
|
|
@max_len_sentences_pair.setter
|
|
def max_len_sentences_pair(self, value) -> int:
|
|
""" For backward compatibility, allow to try to setup 'max_len_sentences_pair' """
|
|
if value == self.model_max_length - self.num_special_tokens_to_add(pair=True) and self.verbose:
|
|
logger.warning(
|
|
"Setting 'max_len_sentences_pair' is now deprecated. " "This value is automatically set up."
|
|
)
|
|
else:
|
|
raise ValueError(
|
|
"Setting 'max_len_sentences_pair' is now deprecated. " "This value is automatically set up."
|
|
)
|
|
|
|
@classmethod
|
|
def from_pretrained(cls, *inputs, **kwargs):
|
|
r"""
|
|
Instantiate a :class:`~transformers.PreTrainedTokenizer` (or a derived class) from a predefined tokenizer.
|
|
|
|
Args:
|
|
pretrained_model_name_or_path: either:
|
|
|
|
- a string with the `shortcut name` of a predefined tokenizer to load from cache or download, e.g.: ``bert-base-uncased``.
|
|
- a string with the `identifier name` of a predefined tokenizer that was user-uploaded to our S3, e.g.: ``dbmdz/bert-base-german-cased``.
|
|
- a path to a `directory` containing vocabulary files required by the tokenizer, for instance saved using the :func:`~transformers.PreTrainedTokenizer.save_pretrained` method, e.g.: ``./my_model_directory/``.
|
|
- (not applicable to all derived classes, deprecated) a path or url to a single saved vocabulary file if and only if the tokenizer only requires a single vocabulary file (e.g. Bert, XLNet), e.g.: ``./my_model_directory/vocab.txt``.
|
|
|
|
cache_dir: (`optional`) string:
|
|
Path to a directory in which a downloaded predefined tokenizer vocabulary files should be cached if the standard cache should not be used.
|
|
|
|
force_download: (`optional`) boolean, default False:
|
|
Force to (re-)download the vocabulary files and override the cached versions if they exists.
|
|
|
|
resume_download: (`optional`) boolean, default False:
|
|
Do not delete incompletely recieved file. Attempt to resume the download if such a file exists.
|
|
|
|
proxies: (`optional`) dict, default None:
|
|
A dictionary of proxy servers to use by protocol or endpoint, e.g.: {'http': 'foo.bar:3128', 'http://hostname': 'foo.bar:4012'}.
|
|
The proxies are used on each request.
|
|
|
|
inputs: (`optional`) positional arguments: will be passed to the Tokenizer ``__init__`` method.
|
|
|
|
kwargs: (`optional`) keyword arguments: will be passed to the Tokenizer ``__init__`` method. Can be used to set special tokens like ``bos_token``, ``eos_token``, ``unk_token``, ``sep_token``, ``pad_token``, ``cls_token``, ``mask_token``, ``additional_special_tokens``. See parameters in the doc string of :class:`~transformers.PreTrainedTokenizer` for details.
|
|
|
|
Examples::
|
|
|
|
# We can't instantiate directly the base class `PreTrainedTokenizer` so let's show our examples on a derived class: BertTokenizer
|
|
|
|
# Download vocabulary from S3 and cache.
|
|
tokenizer = BertTokenizer.from_pretrained('bert-base-uncased')
|
|
|
|
# Download vocabulary from S3 (user-uploaded) and cache.
|
|
tokenizer = BertTokenizer.from_pretrained('dbmdz/bert-base-german-cased')
|
|
|
|
# If vocabulary files are in a directory (e.g. tokenizer was saved using `save_pretrained('./test/saved_model/')`)
|
|
tokenizer = BertTokenizer.from_pretrained('./test/saved_model/')
|
|
|
|
# If the tokenizer uses a single vocabulary file, you can point directly to this file
|
|
tokenizer = BertTokenizer.from_pretrained('./test/saved_model/my_vocab.txt')
|
|
|
|
# You can link tokens to special vocabulary when instantiating
|
|
tokenizer = BertTokenizer.from_pretrained('bert-base-uncased', unk_token='<unk>')
|
|
# You should be sure '<unk>' is in the vocabulary when doing that.
|
|
# Otherwise use tokenizer.add_special_tokens({'unk_token': '<unk>'}) instead)
|
|
assert tokenizer.unk_token == '<unk>'
|
|
|
|
"""
|
|
return cls._from_pretrained(*inputs, **kwargs)
|
|
|
|
@classmethod
|
|
def _from_pretrained(cls, pretrained_model_name_or_path, *init_inputs, **kwargs):
|
|
cache_dir = kwargs.pop("cache_dir", None)
|
|
force_download = kwargs.pop("force_download", False)
|
|
resume_download = kwargs.pop("resume_download", False)
|
|
proxies = kwargs.pop("proxies", None)
|
|
local_files_only = kwargs.pop("local_files_only", False)
|
|
|
|
s3_models = list(cls.max_model_input_sizes.keys())
|
|
vocab_files = {}
|
|
init_configuration = {}
|
|
if pretrained_model_name_or_path in s3_models:
|
|
# Get the vocabulary from AWS S3 bucket
|
|
for file_id, map_list in cls.pretrained_vocab_files_map.items():
|
|
vocab_files[file_id] = map_list[pretrained_model_name_or_path]
|
|
if (
|
|
cls.pretrained_init_configuration
|
|
and pretrained_model_name_or_path in cls.pretrained_init_configuration
|
|
):
|
|
init_configuration = cls.pretrained_init_configuration[pretrained_model_name_or_path].copy()
|
|
else:
|
|
# Get the vocabulary from local files
|
|
logger.info(
|
|
"Model name '{}' not found in model shortcut name list ({}). "
|
|
"Assuming '{}' is a path, a model identifier, or url to a directory containing tokenizer files.".format(
|
|
pretrained_model_name_or_path, ", ".join(s3_models), pretrained_model_name_or_path
|
|
)
|
|
)
|
|
|
|
if os.path.isfile(pretrained_model_name_or_path) or is_remote_url(pretrained_model_name_or_path):
|
|
if len(cls.vocab_files_names) > 1:
|
|
raise ValueError(
|
|
"Calling {}.from_pretrained() with the path to a single file or url is not supported."
|
|
"Use a model identifier or the path to a directory instead.".format(cls.__name__)
|
|
)
|
|
logger.warning(
|
|
"Calling {}.from_pretrained() with the path to a single file or url is deprecated".format(
|
|
cls.__name__
|
|
)
|
|
)
|
|
file_id = list(cls.vocab_files_names.keys())[0]
|
|
vocab_files[file_id] = pretrained_model_name_or_path
|
|
else:
|
|
# At this point pretrained_model_name_or_path is either a directory or a model identifier name
|
|
additional_files_names = {
|
|
"added_tokens_file": ADDED_TOKENS_FILE,
|
|
"special_tokens_map_file": SPECIAL_TOKENS_MAP_FILE,
|
|
"tokenizer_config_file": TOKENIZER_CONFIG_FILE,
|
|
}
|
|
# Look for the tokenizer main vocabulary files + the additional tokens files
|
|
for file_id, file_name in {**cls.vocab_files_names, **additional_files_names}.items():
|
|
if os.path.isdir(pretrained_model_name_or_path):
|
|
full_file_name = os.path.join(pretrained_model_name_or_path, file_name)
|
|
if not os.path.exists(full_file_name):
|
|
logger.info("Didn't find file {}. We won't load it.".format(full_file_name))
|
|
full_file_name = None
|
|
else:
|
|
full_file_name = hf_bucket_url(
|
|
pretrained_model_name_or_path, filename=file_name, use_cdn=False
|
|
)
|
|
|
|
vocab_files[file_id] = full_file_name
|
|
|
|
# Get files from url, cache, or disk depending on the case
|
|
try:
|
|
resolved_vocab_files = {}
|
|
for file_id, file_path in vocab_files.items():
|
|
if file_path is None:
|
|
resolved_vocab_files[file_id] = None
|
|
else:
|
|
resolved_vocab_files[file_id] = cached_path(
|
|
file_path,
|
|
cache_dir=cache_dir,
|
|
force_download=force_download,
|
|
proxies=proxies,
|
|
resume_download=resume_download,
|
|
local_files_only=local_files_only,
|
|
)
|
|
except EnvironmentError:
|
|
if pretrained_model_name_or_path in s3_models:
|
|
msg = "Couldn't reach server at '{}' to download vocabulary files."
|
|
else:
|
|
msg = (
|
|
"Model name '{}' was not found in tokenizers model name list ({}). "
|
|
"We assumed '{}' was a path or url to a directory containing vocabulary files "
|
|
"named {}, but couldn't find such vocabulary files at this path or url.".format(
|
|
pretrained_model_name_or_path,
|
|
", ".join(s3_models),
|
|
pretrained_model_name_or_path,
|
|
list(cls.vocab_files_names.values()),
|
|
)
|
|
)
|
|
|
|
raise EnvironmentError(msg)
|
|
|
|
if all(full_file_name is None for full_file_name in resolved_vocab_files.values()):
|
|
raise EnvironmentError(
|
|
"Model name '{}' was not found in tokenizers model name list ({}). "
|
|
"We assumed '{}' was a path, a model identifier, or url to a directory containing vocabulary files "
|
|
"named {} but couldn't find such vocabulary files at this path or url.".format(
|
|
pretrained_model_name_or_path,
|
|
", ".join(s3_models),
|
|
pretrained_model_name_or_path,
|
|
list(cls.vocab_files_names.values()),
|
|
)
|
|
)
|
|
|
|
for file_id, file_path in vocab_files.items():
|
|
if file_path == resolved_vocab_files[file_id]:
|
|
logger.info("loading file {}".format(file_path))
|
|
else:
|
|
logger.info("loading file {} from cache at {}".format(file_path, resolved_vocab_files[file_id]))
|
|
|
|
# Prepare tokenizer initialization kwargs
|
|
# Did we saved some inputs and kwargs to reload ?
|
|
tokenizer_config_file = resolved_vocab_files.pop("tokenizer_config_file", None)
|
|
if tokenizer_config_file is not None:
|
|
with open(tokenizer_config_file, encoding="utf-8") as tokenizer_config_handle:
|
|
init_kwargs = json.load(tokenizer_config_handle)
|
|
saved_init_inputs = init_kwargs.pop("init_inputs", ())
|
|
if not init_inputs:
|
|
init_inputs = saved_init_inputs
|
|
else:
|
|
init_kwargs = init_configuration
|
|
|
|
# Update with newly provided kwargs
|
|
init_kwargs.update(kwargs)
|
|
|
|
# Set max length if needed
|
|
if pretrained_model_name_or_path in cls.max_model_input_sizes:
|
|
# if we're using a pretrained model, ensure the tokenizer
|
|
# wont index sequences longer than the number of positional embeddings
|
|
model_max_length = cls.max_model_input_sizes[pretrained_model_name_or_path]
|
|
if model_max_length is not None and isinstance(model_max_length, (int, float)):
|
|
init_kwargs["model_max_length"] = min(init_kwargs.get("model_max_length", int(1e30)), model_max_length)
|
|
|
|
# Merge resolved_vocab_files arguments in init_kwargs.
|
|
added_tokens_file = resolved_vocab_files.pop("added_tokens_file", None)
|
|
special_tokens_map_file = resolved_vocab_files.pop("special_tokens_map_file", None)
|
|
for args_name, file_path in resolved_vocab_files.items():
|
|
if args_name not in init_kwargs:
|
|
init_kwargs[args_name] = file_path
|
|
if special_tokens_map_file is not None:
|
|
with open(special_tokens_map_file, encoding="utf-8") as special_tokens_map_handle:
|
|
special_tokens_map = json.load(special_tokens_map_handle)
|
|
for key, value in special_tokens_map.items():
|
|
if key not in init_kwargs:
|
|
init_kwargs[key] = value
|
|
|
|
# Instantiate tokenizer.
|
|
try:
|
|
tokenizer = cls(*init_inputs, **init_kwargs)
|
|
except OSError:
|
|
raise OSError(
|
|
"Unable to load vocabulary from file. "
|
|
"Please check that the provided vocabulary is accessible and not corrupted."
|
|
)
|
|
|
|
# Save inputs and kwargs for saving and re-loading with ``save_pretrained``
|
|
tokenizer.init_inputs = init_inputs
|
|
tokenizer.init_kwargs = init_kwargs
|
|
|
|
# update unique_added_tokens_encoder with special tokens for correct tokenization
|
|
if hasattr(tokenizer, "unique_added_tokens_encoder"):
|
|
tokenizer.unique_added_tokens_encoder.update(set(tokenizer.all_special_tokens))
|
|
|
|
# Add supplementary tokens.
|
|
if added_tokens_file is not None:
|
|
with open(added_tokens_file, encoding="utf-8") as added_tokens_handle:
|
|
added_tok_encoder = json.load(added_tokens_handle)
|
|
added_tok_decoder = {v: k for k, v in added_tok_encoder.items()}
|
|
tokenizer.added_tokens_encoder.update(added_tok_encoder)
|
|
tokenizer.added_tokens_decoder.update(added_tok_decoder)
|
|
tokenizer.unique_added_tokens_encoder.update(set(tokenizer.added_tokens_encoder.keys()))
|
|
|
|
return tokenizer
|
|
|
|
def save_pretrained(self, save_directory) -> Tuple[str]:
|
|
""" Save the tokenizer vocabulary files together with:
|
|
- added tokens,
|
|
- special-tokens-to-class-attributes-mapping,
|
|
- tokenizer instantiation positional and keywords inputs (e.g. do_lower_case for Bert).
|
|
|
|
Warning: This won't save modifications you may have applied to the tokenizer after the instantiation
|
|
(e.g. modifying tokenizer.do_lower_case after creation).
|
|
|
|
This method make sure the full tokenizer can then be re-loaded using the
|
|
:func:`~transformers.PreTrainedTokenizer.from_pretrained` class method.
|
|
"""
|
|
if not os.path.isdir(save_directory):
|
|
logger.error("Saving directory ({}) should be a directory".format(save_directory))
|
|
return
|
|
|
|
special_tokens_map_file = os.path.join(save_directory, SPECIAL_TOKENS_MAP_FILE)
|
|
added_tokens_file = os.path.join(save_directory, ADDED_TOKENS_FILE)
|
|
tokenizer_config_file = os.path.join(save_directory, TOKENIZER_CONFIG_FILE)
|
|
|
|
tokenizer_config = copy.deepcopy(self.init_kwargs)
|
|
if len(self.init_inputs) > 0:
|
|
tokenizer_config["init_inputs"] = copy.deepcopy(self.init_inputs)
|
|
for file_id in self.vocab_files_names.keys():
|
|
tokenizer_config.pop(file_id, None)
|
|
|
|
with open(tokenizer_config_file, "w", encoding="utf-8") as f:
|
|
f.write(json.dumps(tokenizer_config, ensure_ascii=False))
|
|
|
|
with open(special_tokens_map_file, "w", encoding="utf-8") as f:
|
|
f.write(json.dumps(self.special_tokens_map, ensure_ascii=False))
|
|
|
|
if hasattr(self, "added_tokens_encoder") and len(self.added_tokens_encoder) > 0:
|
|
with open(added_tokens_file, "w", encoding="utf-8") as f:
|
|
out_str = json.dumps(self.added_tokens_encoder, ensure_ascii=False)
|
|
f.write(out_str)
|
|
|
|
vocab_files = self.save_vocabulary(save_directory)
|
|
|
|
return vocab_files + (special_tokens_map_file, added_tokens_file)
|
|
|
|
@add_end_docstrings(
|
|
ENCODE_KWARGS_DOCSTRING,
|
|
"""
|
|
**kwargs: passed to the `self.tokenize()` method.
|
|
""",
|
|
)
|
|
def encode(
|
|
self,
|
|
text: Union[TextInput, PreTokenizedInput, EncodedInput],
|
|
text_pair: Optional[Union[TextInput, PreTokenizedInput, EncodedInput]] = None,
|
|
add_special_tokens: bool = True,
|
|
padding: Union[bool, str] = False,
|
|
truncation: Union[bool, str] = False,
|
|
max_length: Optional[int] = None,
|
|
stride: int = 0,
|
|
return_tensors: Optional[Union[str, TensorType]] = None,
|
|
**kwargs
|
|
):
|
|
"""
|
|
Converts a string in a sequence of ids (integer), using the tokenizer and vocabulary.
|
|
|
|
Same as doing ``self.convert_tokens_to_ids(self.tokenize(text))``.
|
|
|
|
Args:
|
|
text (:obj:`str`, :obj:`List[str]` or :obj:`List[int]`):
|
|
The first sequence to be encoded. This can be a string, a list of strings (tokenized string using
|
|
the `tokenize` method) or a list of integers (tokenized string ids using the `convert_tokens_to_ids`
|
|
method)
|
|
text_pair (:obj:`str`, :obj:`List[str]` or :obj:`List[int]`, `optional`, defaults to :obj:`None`):
|
|
Optional second sequence to be encoded. This can be a string, a list of strings (tokenized
|
|
string using the `tokenize` method) or a list of integers (tokenized string ids using the
|
|
`convert_tokens_to_ids` method)
|
|
"""
|
|
encoded_inputs = self.encode_plus(
|
|
text,
|
|
text_pair=text_pair,
|
|
add_special_tokens=add_special_tokens,
|
|
padding=padding,
|
|
truncation=truncation,
|
|
max_length=max_length,
|
|
stride=stride,
|
|
return_tensors=return_tensors,
|
|
**kwargs,
|
|
)
|
|
|
|
return encoded_inputs["input_ids"]
|
|
|
|
def num_special_tokens_to_add(self, pair: bool = False) -> int:
|
|
raise NotImplementedError
|
|
|
|
def _get_padding_truncation_strategies(
|
|
self, padding=False, truncation=False, max_length=None, verbose=True, **kwargs
|
|
):
|
|
""" Find the correct padding/truncation strategy with backward compatibility
|
|
for old arguments (truncation_strategy and pad_to_max_length) and behaviors.
|
|
"""
|
|
old_truncation_strategy = kwargs.pop("truncation_strategy", "do_not_truncate")
|
|
old_pad_to_max_length = kwargs.pop("pad_to_max_length", False)
|
|
|
|
# Backward compatibility for previous behavior, maybe we should deprecate it:
|
|
# If you only set max_length, it activates truncation for max_length
|
|
if max_length is not None and padding is False and truncation is False:
|
|
if verbose:
|
|
logger.warning(
|
|
"Truncation was not explicitely activated but `max_length` is provided a specific value, "
|
|
"please use `truncation=True` to explicitely truncate examples to max length. "
|
|
"Defaulting to 'only_first' truncation strategy. "
|
|
"If you encode pairs of sequences (GLUE-style) with the tokenizer you may want to check this is the right behavior."
|
|
)
|
|
truncation = "only_first"
|
|
|
|
# Get padding strategy
|
|
if padding is False and old_pad_to_max_length:
|
|
if verbose:
|
|
warnings.warn(
|
|
"The `pad_to_max_length` argument is deprecated and will be removed in a future version, "
|
|
"use `padding=True` or `padding='longest'` to pad to the longest sequence in the batch, or "
|
|
"use `padding='max_length'` to pad to a max length. In this case, you can give a specific "
|
|
"length with `max_length` (e.g. `max_length=45`) or leave max_length to None to pad to the "
|
|
"maximal input size of the model (e.g. 512 for Bert).",
|
|
DeprecationWarning,
|
|
)
|
|
if max_length is None:
|
|
padding_strategy = PaddingStrategy.LONGEST
|
|
else:
|
|
padding_strategy = PaddingStrategy.MAX_LENGTH
|
|
elif padding is not False:
|
|
if padding is True:
|
|
padding_strategy = PaddingStrategy.LONGEST # Default to pad to the longest sequence in the batch
|
|
else:
|
|
padding_strategy = PaddingStrategy(padding)
|
|
else:
|
|
padding_strategy = PaddingStrategy.DO_NOT_PAD
|
|
|
|
# Get truncation strategy
|
|
if truncation is False and old_truncation_strategy != "do_not_truncate":
|
|
if verbose:
|
|
warnings.warn(
|
|
"The `truncation_strategy` argument is deprecated and will be removed in a future version, "
|
|
"use `truncation=True` to truncate examples to a max length. You can give a specific "
|
|
"length with `max_length` (e.g. `max_length=45`) or leave max_length to None to truncate to the "
|
|
"maximal input size of the model (e.g. 512 for Bert). "
|
|
" If you have pairs of inputs, you can give a specific truncation strategy selected among "
|
|
"`truncation='only_first'` (will only truncate the first sentence in the pairs) "
|
|
"`truncation='only_second'` (will only truncate the second sentence in the pairs) "
|
|
"or `truncation='longest_first'` (will iteratively remove tokens from the longest sentence in the pairs).",
|
|
DeprecationWarning,
|
|
)
|
|
truncation_strategy = TruncationStrategy(old_truncation_strategy)
|
|
elif truncation is not False:
|
|
if truncation is True:
|
|
truncation_strategy = (
|
|
TruncationStrategy.ONLY_FIRST
|
|
) # Default to truncate the first sequences in pairs of inputs
|
|
else:
|
|
truncation_strategy = TruncationStrategy(truncation)
|
|
else:
|
|
truncation_strategy = TruncationStrategy.DO_NOT_TRUNCATE
|
|
|
|
# Set max length if needed
|
|
if max_length is None:
|
|
if padding_strategy == PaddingStrategy.MAX_LENGTH:
|
|
if self.model_max_length > LARGE_INTEGER:
|
|
if verbose:
|
|
logger.warning(
|
|
"Asking to pad to max_length but no maximum length is provided and the model has no predefined maximum length. "
|
|
"Default to no padding."
|
|
)
|
|
padding_strategy = PaddingStrategy.DO_NOT_PAD
|
|
else:
|
|
max_length = self.model_max_length
|
|
|
|
if truncation_strategy != TruncationStrategy.DO_NOT_TRUNCATE:
|
|
if self.model_max_length > LARGE_INTEGER:
|
|
if verbose:
|
|
logger.warning(
|
|
"Asking to truncate to max_length but no maximum length is provided and the model has no predefined maximum length. "
|
|
"Default to no truncation."
|
|
)
|
|
truncation_strategy = TruncationStrategy.DO_NOT_TRUNCATE
|
|
else:
|
|
max_length = self.model_max_length
|
|
|
|
# Test if we have a padding token
|
|
if padding_strategy != PaddingStrategy.DO_NOT_PAD and (not self.pad_token or self.pad_token_id < 0):
|
|
raise ValueError(
|
|
"Asking to pad but the tokenizer does not have a padding token. "
|
|
"Please select a token to use as `pad_token` `(tokenizer.pad_token = tokenizer.eos_token e.g.)` "
|
|
"or add a new pad token via `tokenizer.add_special_tokens({'pad_token': '[PAD]'})`."
|
|
)
|
|
|
|
return padding_strategy, truncation_strategy, max_length, kwargs
|
|
|
|
@add_end_docstrings(ENCODE_KWARGS_DOCSTRING, ENCODE_PLUS_ADDITIONAL_KWARGS_DOCSTRING)
|
|
def __call__(
|
|
self,
|
|
text: Union[TextInput, PreTokenizedInput, List[TextInput], List[PreTokenizedInput]],
|
|
text_pair: Optional[Union[TextInput, PreTokenizedInput, List[TextInput], List[PreTokenizedInput]]] = None,
|
|
add_special_tokens: bool = True,
|
|
padding: Union[bool, str] = False,
|
|
truncation: Union[bool, str] = False,
|
|
max_length: Optional[int] = None,
|
|
stride: int = 0,
|
|
is_pretokenized: bool = False,
|
|
return_tensors: Optional[Union[str, TensorType]] = None,
|
|
return_token_type_ids: Optional[bool] = None,
|
|
return_attention_mask: Optional[bool] = None,
|
|
return_overflowing_tokens: bool = False,
|
|
return_special_tokens_mask: bool = False,
|
|
return_offsets_mapping: bool = False,
|
|
return_lengths: bool = False,
|
|
verbose: bool = True,
|
|
**kwargs
|
|
) -> BatchEncoding:
|
|
"""
|
|
Returns a dictionary containing the encoded sequence or sequence pair and additional information:
|
|
the mask for sequence classification and the overflowing elements if a ``max_length`` is specified.
|
|
|
|
Args:
|
|
text (:obj:`str`, :obj:`List[str]`, :obj:`List[List[str]]``):
|
|
The sequence or batch of sequences to be encoded.
|
|
Each sequence can be a string or a list of strings (pre-tokenized string).
|
|
If the sequences are provided as list of strings (pretokenized), you must set `is_pretokenized=True`
|
|
(to lift the ambiguity with a batch of sequences)
|
|
text_pair (:obj:`str`, :obj:`List[str]`, :obj:`List[List[str]]``):
|
|
The sequence or batch of sequences to be encoded.
|
|
Each sequence can be a string or a list of strings (pre-tokenized string).
|
|
If the sequences are provided as list of strings (pretokenized), you must set `is_pretokenized=True`
|
|
(to lift the ambiguity with a batch of sequences)
|
|
"""
|
|
is_batched = bool(
|
|
(not is_pretokenized and isinstance(text, (list, tuple)))
|
|
or (is_pretokenized and isinstance(text, (list, tuple)) and text and isinstance(text[0], (list, tuple)))
|
|
)
|
|
|
|
if is_batched:
|
|
batch_text_or_text_pairs = list(zip(text, text_pair)) if text_pair is not None else text
|
|
return self.batch_encode_plus(
|
|
batch_text_or_text_pairs=batch_text_or_text_pairs,
|
|
add_special_tokens=add_special_tokens,
|
|
padding=padding,
|
|
truncation=truncation,
|
|
max_length=max_length,
|
|
stride=stride,
|
|
is_pretokenized=is_pretokenized,
|
|
return_tensors=return_tensors,
|
|
return_token_type_ids=return_token_type_ids,
|
|
return_attention_masks=return_attention_mask,
|
|
return_overflowing_tokens=return_overflowing_tokens,
|
|
return_special_tokens_masks=return_special_tokens_mask,
|
|
return_offsets_mapping=return_offsets_mapping,
|
|
return_lengths=return_lengths,
|
|
verbose=verbose,
|
|
**kwargs,
|
|
)
|
|
else:
|
|
return self.encode_plus(
|
|
text=text,
|
|
text_pair=text_pair,
|
|
add_special_tokens=add_special_tokens,
|
|
padding=padding,
|
|
truncation=truncation,
|
|
max_length=max_length,
|
|
stride=stride,
|
|
is_pretokenized=is_pretokenized,
|
|
return_tensors=return_tensors,
|
|
return_token_type_ids=return_token_type_ids,
|
|
return_attention_mask=return_attention_mask,
|
|
return_overflowing_tokens=return_overflowing_tokens,
|
|
return_special_tokens_mask=return_special_tokens_mask,
|
|
return_offsets_mapping=return_offsets_mapping,
|
|
verbose=verbose,
|
|
**kwargs,
|
|
)
|
|
|
|
@add_end_docstrings(ENCODE_KWARGS_DOCSTRING, ENCODE_PLUS_ADDITIONAL_KWARGS_DOCSTRING)
|
|
def encode_plus(
|
|
self,
|
|
text: Union[TextInput, PreTokenizedInput, EncodedInput],
|
|
text_pair: Optional[Union[TextInput, PreTokenizedInput, EncodedInput]] = None,
|
|
add_special_tokens: bool = True,
|
|
padding: Union[bool, str] = False,
|
|
truncation: Union[bool, str] = False,
|
|
max_length: Optional[int] = None,
|
|
stride: int = 0,
|
|
is_pretokenized: bool = False,
|
|
return_tensors: Optional[Union[str, TensorType]] = None,
|
|
return_token_type_ids: Optional[bool] = None,
|
|
return_attention_mask: Optional[bool] = None,
|
|
return_overflowing_tokens: bool = False,
|
|
return_special_tokens_mask: bool = False,
|
|
return_offsets_mapping: bool = False,
|
|
return_lengths: bool = False,
|
|
verbose: bool = True,
|
|
**kwargs
|
|
) -> BatchEncoding:
|
|
"""
|
|
Returns a dictionary containing the encoded sequence or sequence pair and additional information:
|
|
the mask for sequence classification and the overflowing elements if a ``max_length`` is specified.
|
|
|
|
Args:
|
|
text (:obj:`str`, :obj:`List[str]` or :obj:`List[int]` (the later only for not-fast tokenizers)):
|
|
The first sequence to be encoded. This can be a string, a list of strings (tokenized string using
|
|
the `tokenize` method) or a list of integers (tokenized string ids using the `convert_tokens_to_ids`
|
|
method)
|
|
text_pair (:obj:`str`, :obj:`List[str]` or :obj:`List[int]`, `optional`, defaults to :obj:`None`):
|
|
Optional second sequence to be encoded. This can be a string, a list of strings (tokenized
|
|
string using the `tokenize` method) or a list of integers (tokenized string ids using the
|
|
`convert_tokens_to_ids` method)
|
|
"""
|
|
|
|
# Backward compatibility for 'truncation_strategy', 'pad_to_max_length'
|
|
padding_strategy, truncation_strategy, max_length, kwargs = self._get_padding_truncation_strategies(
|
|
padding, truncation, max_length, verbose, **kwargs
|
|
)
|
|
|
|
return self._encode_plus(
|
|
text=text,
|
|
text_pair=text_pair,
|
|
add_special_tokens=add_special_tokens,
|
|
padding_strategy=padding_strategy,
|
|
truncation_strategy=truncation_strategy,
|
|
max_length=max_length,
|
|
stride=stride,
|
|
is_pretokenized=is_pretokenized,
|
|
return_tensors=return_tensors,
|
|
return_token_type_ids=return_token_type_ids,
|
|
return_attention_mask=return_attention_mask,
|
|
return_overflowing_tokens=return_overflowing_tokens,
|
|
return_special_tokens_mask=return_special_tokens_mask,
|
|
return_offsets_mapping=return_offsets_mapping,
|
|
return_lengths=return_lengths,
|
|
verbose=verbose,
|
|
**kwargs,
|
|
)
|
|
|
|
def _encode_plus(
|
|
self,
|
|
text: Union[TextInput, PreTokenizedInput, EncodedInput],
|
|
text_pair: Optional[Union[TextInput, PreTokenizedInput, EncodedInput]] = None,
|
|
add_special_tokens: bool = True,
|
|
padding_strategy: PaddingStrategy = PaddingStrategy.DO_NOT_PAD,
|
|
truncation_strategy: TruncationStrategy = TruncationStrategy.DO_NOT_TRUNCATE,
|
|
max_length: Optional[int] = None,
|
|
stride: int = 0,
|
|
is_pretokenized: bool = False,
|
|
return_tensors: Optional[Union[str, TensorType]] = None,
|
|
return_token_type_ids: Optional[bool] = None,
|
|
return_attention_mask: Optional[bool] = None,
|
|
return_overflowing_tokens: bool = False,
|
|
return_special_tokens_mask: bool = False,
|
|
return_offsets_mapping: bool = False,
|
|
verbose: bool = True,
|
|
**kwargs
|
|
) -> BatchEncoding:
|
|
raise NotImplementedError
|
|
|
|
@add_end_docstrings(ENCODE_KWARGS_DOCSTRING, ENCODE_PLUS_ADDITIONAL_KWARGS_DOCSTRING)
|
|
def batch_encode_plus(
|
|
self,
|
|
batch_text_or_text_pairs: Union[
|
|
List[TextInput],
|
|
List[TextInputPair],
|
|
List[PreTokenizedInput],
|
|
List[PreTokenizedInputPair],
|
|
List[EncodedInput],
|
|
List[EncodedInputPair],
|
|
],
|
|
add_special_tokens: bool = True,
|
|
padding: Union[bool, str] = False,
|
|
truncation: Union[bool, str] = False,
|
|
max_length: Optional[int] = None,
|
|
stride: int = 0,
|
|
is_pretokenized: bool = False,
|
|
return_tensors: Optional[Union[str, TensorType]] = None,
|
|
return_token_type_ids: Optional[bool] = None,
|
|
return_attention_masks: Optional[bool] = None,
|
|
return_overflowing_tokens: bool = False,
|
|
return_special_tokens_masks: bool = False,
|
|
return_offsets_mapping: bool = False,
|
|
return_lengths: bool = False,
|
|
verbose: bool = True,
|
|
**kwargs
|
|
) -> BatchEncoding:
|
|
"""
|
|
Returns a dictionary containing the encoded sequence or sequence pair and additional information:
|
|
the mask for sequence classification and the overflowing elements if a ``max_length`` is specified.
|
|
|
|
Args:
|
|
batch_text_or_text_pairs (:obj:`List[str]`, :obj:`List[Tuple[str, str]]`,
|
|
:obj:`List[List[str]]`, :obj:`List[Tuple[List[str], List[str]]]`,
|
|
and for not-fast tokenizers, also:
|
|
:obj:`List[List[int]]`, :obj:`List[Tuple[List[int], List[int]]]`):
|
|
Batch of sequences or pair of sequences to be encoded.
|
|
This can be a list of string/string-sequences/int-sequences or a list of pair of
|
|
string/string-sequences/int-sequence (see details in encode_plus)
|
|
"""
|
|
|
|
# Backward compatibility for 'truncation_strategy', 'pad_to_max_length'
|
|
padding_strategy, truncation_strategy, max_length, kwargs = self._get_padding_truncation_strategies(
|
|
padding, truncation, max_length, verbose, **kwargs
|
|
)
|
|
|
|
return self._batch_encode_plus(
|
|
batch_text_or_text_pairs=batch_text_or_text_pairs,
|
|
add_special_tokens=add_special_tokens,
|
|
padding_strategy=padding_strategy,
|
|
truncation_strategy=truncation_strategy,
|
|
max_length=max_length,
|
|
stride=stride,
|
|
is_pretokenized=is_pretokenized,
|
|
return_tensors=return_tensors,
|
|
return_token_type_ids=return_token_type_ids,
|
|
return_attention_masks=return_attention_masks,
|
|
return_overflowing_tokens=return_overflowing_tokens,
|
|
return_special_tokens_masks=return_special_tokens_masks,
|
|
return_offsets_mapping=return_offsets_mapping,
|
|
return_lengths=return_lengths,
|
|
verbose=verbose,
|
|
**kwargs,
|
|
)
|
|
|
|
def _batch_encode_plus(
|
|
self,
|
|
batch_text_or_text_pairs: Union[
|
|
List[TextInput],
|
|
List[TextInputPair],
|
|
List[PreTokenizedInput],
|
|
List[PreTokenizedInputPair],
|
|
List[EncodedInput],
|
|
List[EncodedInputPair],
|
|
],
|
|
add_special_tokens: bool = True,
|
|
padding_strategy: PaddingStrategy = PaddingStrategy.DO_NOT_PAD,
|
|
truncation_strategy: TruncationStrategy = TruncationStrategy.DO_NOT_TRUNCATE,
|
|
max_length: Optional[int] = None,
|
|
stride: int = 0,
|
|
is_pretokenized: bool = False,
|
|
return_tensors: Optional[Union[str, TensorType]] = None,
|
|
return_token_type_ids: Optional[bool] = None,
|
|
return_attention_masks: Optional[bool] = None,
|
|
return_overflowing_tokens: bool = False,
|
|
return_special_tokens_masks: bool = False,
|
|
return_offsets_mapping: bool = False,
|
|
return_lengths: bool = False,
|
|
verbose: bool = True,
|
|
**kwargs
|
|
) -> BatchEncoding:
|
|
raise NotImplementedError
|
|
|
|
def pad(
|
|
self,
|
|
encoding_or_batch: Dict[str, Union[List[EncodedInput], EncodedInput]],
|
|
padding: Union[bool, str] = True,
|
|
max_length: Optional[int] = None,
|
|
return_attention_mask: Optional[bool] = None,
|
|
verbose: bool = True,
|
|
) -> dict:
|
|
""" Pad encoded inputs (on left/right and up to predefined legnth or max length in the batch)
|
|
|
|
Args:
|
|
batch_ids: Dictionary of batch of tokenized inputs (`List[List[int]]`).
|
|
max_length: maximum length of the returned list and optionally padding length (see below).
|
|
Will truncate by taking into account the special tokens.
|
|
padding: Boolean or specific strategy to use for padding.
|
|
Select a strategy to pad the returned sequences (according to the model's padding side and padding index) among:
|
|
- 'longest' (or `True`) Pad to the longest sequence in the batch
|
|
- 'max_length': Pad to the max length (default)
|
|
- 'do_not_pad' (or `False`): Do not pad
|
|
The tokenizer padding sides are defined in self.padding_side:
|
|
- 'left': pads on the left of the sequences
|
|
- 'right': pads on the right of the sequences
|
|
return_attention_mask: (optional) Set to False to avoid returning attention mask (default: set to model specifics)
|
|
"""
|
|
assert "input_ids" in encoding_or_batch, (
|
|
"You should supply an encoding to this method (a dict of lists/batch of int). "
|
|
"This is the output of encode/encode_plus/batch_encode_plus/__call__. "
|
|
)
|
|
|
|
if not encoding_or_batch["input_ids"]:
|
|
if return_attention_mask:
|
|
encoding_or_batch["attention_mask"] = []
|
|
return encoding_or_batch
|
|
|
|
# Backward compatibility for 'truncation_strategy', 'pad_to_max_length'
|
|
padding_strategy, _, max_length, _ = self._get_padding_truncation_strategies(
|
|
padding=padding, max_length=max_length, verbose=verbose
|
|
)
|
|
|
|
if encoding_or_batch["input_ids"] and not isinstance(encoding_or_batch["input_ids"][0], (list, tuple)):
|
|
return self._pad(
|
|
encoding_or_batch,
|
|
max_length=max_length,
|
|
padding_strategy=padding_strategy,
|
|
return_attention_mask=return_attention_mask,
|
|
)
|
|
|
|
batch_size = len(encoding_or_batch["input_ids"])
|
|
assert all(
|
|
len(v) == batch_size for v in encoding_or_batch.values()
|
|
), "Some items in the output dictionnary have a different batch size than others."
|
|
|
|
if padding_strategy == PaddingStrategy.LONGEST:
|
|
max_length = max(len(inputs) for inputs in encoding_or_batch["input_ids"])
|
|
padding_strategy = PaddingStrategy.MAX_LENGTH
|
|
|
|
batch_outputs = {}
|
|
for i in range(batch_size):
|
|
inputs = dict((k, v[i]) for k, v in encoding_or_batch.items())
|
|
outputs = self._pad(
|
|
inputs,
|
|
max_length=max_length,
|
|
padding_strategy=padding_strategy,
|
|
return_attention_mask=return_attention_mask,
|
|
)
|
|
|
|
for key, value in outputs.items():
|
|
if key not in batch_outputs:
|
|
batch_outputs[key] = []
|
|
batch_outputs[key].append(value)
|
|
|
|
return batch_outputs
|
|
|
|
def _pad(
|
|
self,
|
|
encoded_inputs: Dict[str, EncodedInput],
|
|
max_length: Optional[int] = None,
|
|
padding_strategy: PaddingStrategy = PaddingStrategy.DO_NOT_PAD,
|
|
return_attention_mask: Optional[bool] = None,
|
|
) -> dict:
|
|
""" Pad encoded inputs (on left/right and up to predefined legnth or max length in the batch)
|
|
|
|
Args:
|
|
encoded_inputs: Dictionary of tokenized inputs (`List[int]`) or batch of tokenized inputs (`List[List[int]]`).
|
|
max_length: maximum length of the returned list and optionally padding length (see below).
|
|
Will truncate by taking into account the special tokens.
|
|
padding_strategy: PaddingStrategy to use for padding.
|
|
- PaddingStrategy.LONGEST Pad to the longest sequence in the batch
|
|
- PaddingStrategy.MAX_LENGTH: Pad to the max length (default)
|
|
- PaddingStrategy.DO_NOT_PAD: Do not pad
|
|
The tokenizer padding sides are defined in self.padding_side:
|
|
- 'left': pads on the left of the sequences
|
|
- 'right': pads on the right of the sequences
|
|
return_attention_mask: (optional) Set to False to avoid returning attention mask (default: set to model specifics)
|
|
"""
|
|
# Load from model defaults
|
|
if return_attention_mask is None:
|
|
return_attention_mask = "attention_mask" in self.model_input_names
|
|
|
|
if padding_strategy == PaddingStrategy.LONGEST and max_length is None:
|
|
max_length = len(encoded_inputs["input_ids"])
|
|
|
|
needs_to_be_padded = (
|
|
padding_strategy != PaddingStrategy.DO_NOT_PAD and len(encoded_inputs["input_ids"]) != max_length
|
|
)
|
|
|
|
if needs_to_be_padded:
|
|
difference = max_length - len(encoded_inputs["input_ids"])
|
|
if self.padding_side == "right":
|
|
if return_attention_mask:
|
|
encoded_inputs["attention_mask"] = [1] * len(encoded_inputs["input_ids"]) + [0] * difference
|
|
if "token_type_ids" in encoded_inputs:
|
|
encoded_inputs["token_type_ids"] = (
|
|
encoded_inputs["token_type_ids"] + [self.pad_token_type_id] * difference
|
|
)
|
|
if "special_tokens_mask" in encoded_inputs:
|
|
encoded_inputs["special_tokens_mask"] = encoded_inputs["special_tokens_mask"] + [1] * difference
|
|
encoded_inputs["input_ids"] = encoded_inputs["input_ids"] + [self.pad_token_id] * difference
|
|
elif self.padding_side == "left":
|
|
if return_attention_mask:
|
|
encoded_inputs["attention_mask"] = [0] * difference + [1] * len(encoded_inputs["input_ids"])
|
|
if "token_type_ids" in encoded_inputs:
|
|
encoded_inputs["token_type_ids"] = [self.pad_token_type_id] * difference + encoded_inputs[
|
|
"token_type_ids"
|
|
]
|
|
if "special_tokens_mask" in encoded_inputs:
|
|
encoded_inputs["special_tokens_mask"] = [1] * difference + encoded_inputs["special_tokens_mask"]
|
|
encoded_inputs["input_ids"] = [self.pad_token_id] * difference + encoded_inputs["input_ids"]
|
|
else:
|
|
raise ValueError("Invalid padding strategy:" + str(self.padding_side))
|
|
else:
|
|
if return_attention_mask:
|
|
encoded_inputs["attention_mask"] = [1] * len(encoded_inputs["input_ids"])
|
|
|
|
return encoded_inputs
|
|
|
|
def batch_decode(self, sequences: List[List[int]], **kwargs) -> List[str]:
|
|
return [self.decode(seq, **kwargs) for seq in sequences]
|
|
|
|
@staticmethod
|
|
def clean_up_tokenization(out_string: str) -> str:
|
|
""" Clean up a list of simple English tokenization artifacts like spaces before punctuations and abreviated forms.
|
|
"""
|
|
out_string = (
|
|
out_string.replace(" .", ".")
|
|
.replace(" ?", "?")
|
|
.replace(" !", "!")
|
|
.replace(" ,", ",")
|
|
.replace(" ' ", "'")
|
|
.replace(" n't", "n't")
|
|
.replace(" 'm", "'m")
|
|
.replace(" 's", "'s")
|
|
.replace(" 've", "'ve")
|
|
.replace(" 're", "'re")
|
|
)
|
|
return out_string
|