File size: 7,002 Bytes
b6e0ef8 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 | from __future__ import annotations
from typing import Any
import tiktoken
from transformers import PreTrainedTokenizer
import tiktoken
class _SteerlingTokenizer:
"""
Tokenizer for Steerling models.
Uses tiktoken cl100k_base with custom special tokens.
Pass ``instruct=True`` to include the 3 additional chat tokens
used by the instruct model.
"""
ENCODING_NAME = 'cl100k_base'
def __init__(self, instruct: bool=False):
base_enc = tiktoken.get_encoding(self.ENCODING_NAME)
base_vocab = base_enc.n_vocab
self._pad_token_id = base_vocab
self._bos_token_id = base_vocab + 1
self._endofchunk_token_id = base_vocab + 2
self._mask_token_id = base_vocab + 3
self._eos_token_id = base_enc._special_tokens['<|endoftext|>']
self._instruct = instruct
special_tokens = {**base_enc._special_tokens, '<|pad|>': self._pad_token_id, '<|bos|>': self._bos_token_id, '<|endofchunk|>': self._endofchunk_token_id, '<|mask|>': self._mask_token_id}
if instruct:
self._start_header_id = base_vocab + 4
self._end_header_id = base_vocab + 5
self._eot_id = base_vocab + 6
self._vocab_size = base_vocab + 7
special_tokens.update({'<|start_header_id|>': self._start_header_id, '<|end_header_id|>': self._end_header_id, '<|eot_id|>': self._eot_id})
else:
self._start_header_id = None
self._end_header_id = None
self._eot_id = None
self._vocab_size = base_vocab + 4
self._tokenizer = tiktoken.Encoding(name=f'{self.ENCODING_NAME}_steerling', pat_str=base_enc._pat_str, mergeable_ranks=base_enc._mergeable_ranks, special_tokens=special_tokens)
self._special_token_ids = {self._pad_token_id, self._bos_token_id, self._eos_token_id, self._endofchunk_token_id, self._mask_token_id}
if instruct:
self._special_token_ids.update({self._start_header_id, self._end_header_id, self._eot_id})
def encode(self, text: str, add_special_tokens: bool=True) -> list[int]:
"""
Encode text to token IDs.
Args:
text: Input text
add_special_tokens: If True, prepend BOS and append EOS
Returns:
List of token IDs
"""
tokens = self._tokenizer.encode(text, disallowed_special=())
if add_special_tokens:
tokens = [self._bos_token_id] + tokens + [self._eos_token_id]
return tokens
def decode(self, tokens: list[int], skip_special_tokens: bool=True) -> str:
"""
Decode token IDs to text.
Args:
tokens: Token IDs (list, numpy array, or torch tensor)
skip_special_tokens: If True, filter out special tokens before decoding
Returns:
Decoded text
"""
if skip_special_tokens:
tokens = [int(t) for t in tokens if int(t) not in self._special_token_ids]
else:
tokens = [int(t) for t in tokens]
return self._tokenizer.decode(tokens)
@property
def vocab_size(self) -> int:
return self._vocab_size
@property
def pad_token_id(self) -> int:
return self._pad_token_id
@property
def bos_token_id(self) -> int:
return self._bos_token_id
@property
def eos_token_id(self) -> int:
return self._eos_token_id
@property
def endofchunk_token_id(self) -> int:
return self._endofchunk_token_id
@property
def mask_token_id(self) -> int:
return self._mask_token_id
@property
def instruct(self) -> bool:
return self._instruct
@property
def start_header_id(self) -> int | None:
return self._start_header_id
@property
def end_header_id(self) -> int | None:
return self._end_header_id
@property
def eot_id(self) -> int | None:
return self._eot_id
class SteerlingTokenizer(PreTrainedTokenizer):
vocab_files_names: dict[str, str] = {}
model_input_names = ["input_ids", "attention_mask"]
def __init__(self, encoding_name="cl100k_base", pad_token_id=100277,
bos_token_id=100278, eos_token_id=100257,
endofchunk_token_id=100279, mask_token_id=100280, **kwargs):
self._core = _SteerlingTokenizer(instruct=True)
self._endofchunk_token_id = endofchunk_token_id
self._mask_token_id = mask_token_id
for k in ("pad_token", "bos_token", "eos_token", "additional_special_tokens"):
kwargs.pop(k, None)
super().__init__(pad_token="<|pad|>", bos_token="<|bos|>", eos_token="<|endoftext|>",
additional_special_tokens=["<|endofchunk|>", "<|mask|>", "<|start_header_id|>", "<|end_header_id|>", "<|eot_id|>"], **kwargs)
@property
def vocab_size(self): return self._core.vocab_size
@property
def endofchunk_token_id(self): return self._core.endofchunk_token_id
@property
def mask_token_id(self): return self._core.mask_token_id
@property
def start_header_id(self): return self._core.start_header_id
@property
def end_header_id(self): return self._core.end_header_id
@property
def eot_id(self): return self._core.eot_id
def get_vocab(self): return dict(self._core._tokenizer._special_tokens)
def _tokenize(self, text, **kwargs):
return [str(i) for i in self._core._tokenizer.encode(text, disallowed_special=())]
def _convert_token_to_id(self, token):
special = self._core._tokenizer._special_tokens
if token in special: return special[token]
try: return int(token)
except ValueError:
ids = self._core._tokenizer.encode(token, disallowed_special=())
return ids[0] if ids else self._core.pad_token_id
def _convert_id_to_token(self, index):
for name, idx in self._core._tokenizer._special_tokens.items():
if idx == index: return name
try: return self._core._tokenizer.decode([index])
except Exception: return f"<|token_{index}|>"
def convert_tokens_to_string(self, tokens):
ids, special = [], self._core._tokenizer._special_tokens
for t in tokens:
if t in special: continue
try:
tid = int(t)
if tid not in self._core._special_token_ids: ids.append(tid)
except ValueError:
ids.extend(self._core._tokenizer.encode(t, disallowed_special=()))
return self._core._tokenizer.decode(ids)
def _decode(self, token_ids, skip_special_tokens=False, **kwargs):
return self._core.decode(list(token_ids) if not isinstance(token_ids, list) else token_ids,
skip_special_tokens=skip_special_tokens)
def build_inputs_with_special_tokens(self, token_ids_0, token_ids_1=None):
return token_ids_0
def save_vocabulary(self, save_directory, filename_prefix=None):
return ()
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