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config.json ADDED
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+ {
2
+ "architectures": [
3
+ "LtgBertForMaskedLM"
4
+ ],
5
+ "attention_probs_dropout_prob": 0.1,
6
+ "auto_map": {
7
+ "AutoConfig": "configuration_ltgbert.LtgBertConfig",
8
+ "AutoModel": "modeling_ltgbert.LtgBertModel",
9
+ "AutoModelForMaskedLM": "modeling_ltgbert.LtgBertForMaskedLM",
10
+ "AutoModelForSequenceClassification": "modeling_ltgbert.LtgBertForSequenceClassification"
11
+ },
12
+ "classifier_dropout": 0.2,
13
+ "hidden_dropout_prob": 0.1,
14
+ "hidden_size": 768,
15
+ "intermediate_size": 2048,
16
+ "layer_norm_eps": 1e-07,
17
+ "max_position_embeddings": 512,
18
+ "model_type": "ltgbert",
19
+ "num_attention_heads": 12,
20
+ "num_hidden_layers": 12,
21
+ "output_all_encoded_layers": true,
22
+ "pad_token_id": 4,
23
+ "position_bucket_size": 32,
24
+ "torch_dtype": "float32",
25
+ "transformers_version": "4.26.0",
26
+ "vocab_size": 16384
27
+ }
configuration_ltgbert.py ADDED
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1
+ # coding=utf-8
2
+ # Copyright 2023 Language Technology Group from University of Oslo and The HuggingFace Inc. team.
3
+ #
4
+ # Licensed under the Apache License, Version 2.0 (the "License");
5
+ # you may not use this file except in compliance with the License.
6
+ # You may obtain a copy of the License at
7
+ #
8
+ # http://www.apache.org/licenses/LICENSE-2.0
9
+ #
10
+ # Unless required by applicable law or agreed to in writing, software
11
+ # distributed under the License is distributed on an "AS IS" BASIS,
12
+ # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13
+ # See the License for the specific language governing permissions and
14
+ # limitations under the License.
15
+
16
+ """ LTG-BERT configutation """
17
+
18
+
19
+ from transformers.configuration_utils import PretrainedConfig
20
+
21
+
22
+ LTG_BERT_PRETRAINED_CONFIG_ARCHIVE_MAP = {
23
+ "bnc-bert-span": "https://huggingface.co/ltg/bnc-bert-span",
24
+ "bnc-bert-span-2x": "https://huggingface.co/ltg/bnc-bert-span-2x",
25
+ "bnc-bert-span-0.5x": "https://huggingface.co/ltg/bnc-bert-span-0.5x",
26
+ "bnc-bert-span-0.25x": "https://huggingface.co/ltg/bnc-bert-span-0.25x",
27
+ "bnc-bert-span-order": "https://huggingface.co/ltg/bnc-bert-span-order",
28
+ "bnc-bert-span-document": "https://huggingface.co/ltg/bnc-bert-span-document",
29
+ "bnc-bert-span-word": "https://huggingface.co/ltg/bnc-bert-span-word",
30
+ "bnc-bert-span-subword": "https://huggingface.co/ltg/bnc-bert-span-subword",
31
+
32
+ "norbert3-xs": "https://huggingface.co/ltg/norbert3-xs/config.json",
33
+ "norbert3-small": "https://huggingface.co/ltg/norbert3-small/config.json",
34
+ "norbert3-base": "https://huggingface.co/ltg/norbert3-base/config.json",
35
+ "norbert3-large": "https://huggingface.co/ltg/norbert3-large/config.json",
36
+
37
+ "norbert3-oversampled-base": "https://huggingface.co/ltg/norbert3-oversampled-base/config.json",
38
+ "norbert3-ncc-base": "https://huggingface.co/ltg/norbert3-ncc-base/config.json",
39
+ "norbert3-nak-base": "https://huggingface.co/ltg/norbert3-nak-base/config.json",
40
+ "norbert3-nb-base": "https://huggingface.co/ltg/norbert3-nb-base/config.json",
41
+ "norbert3-wiki-base": "https://huggingface.co/ltg/norbert3-wiki-base/config.json",
42
+ "norbert3-c4-base": "https://huggingface.co/ltg/norbert3-c4-base/config.json"
43
+ }
44
+
45
+
46
+ class LtgBertConfig(PretrainedConfig):
47
+ r"""
48
+ This is the configuration class to store the configuration of a [`LtgBertModel`]. It is used to
49
+ instantiate an LTG-BERT model according to the specified arguments, defining the model architecture.
50
+ Configuration objects inherit from [`PretrainedConfig`] and can be used to control the model outputs. Read the
51
+ documentation from [`PretrainedConfig`] for more information.
52
+ Args:
53
+ vocab_size (`int`, *optional*, defaults to 16384):
54
+ Vocabulary size of the LTG-BERT model. Defines the number of different tokens that can be represented by the
55
+ `inputs_ids` passed when calling [`LtgBertModel`].
56
+ hidden_size (`int`, *optional*, defaults to 768):
57
+ Dimensionality of the encoder layers and the pooler layer.
58
+ num_hidden_layers (`int`, *optional*, defaults to 12):
59
+ Number of hidden layers in the Transformer encoder.
60
+ num_attention_heads (`int`, *optional*, defaults to 12):
61
+ Number of attention heads for each attention layer in the Transformer encoder.
62
+ intermediate_size (`int`, *optional*, defaults to 2048):
63
+ Dimensionality of the "intermediate" (often named feed-forward) layer in the Transformer encoder.
64
+ hidden_dropout_prob (`float`, *optional*, defaults to 0.1):
65
+ The dropout probability for all fully connected layers in the embeddings, encoder, and pooler.
66
+ attention_probs_dropout_prob (`float`, *optional*, defaults to 0.1):
67
+ The dropout ratio for the attention probabilities.
68
+ max_position_embeddings (`int`, *optional*, defaults to 512):
69
+ The maximum sequence length that this model might ever be used with. Typically set this to something large
70
+ just in case (e.g., 512 or 1024 or 2048).
71
+ layer_norm_eps (`float`, *optional*, defaults to 1e-12):
72
+ The epsilon used by the layer normalization layers.
73
+ classifier_dropout (`float`, *optional*):
74
+ The dropout ratio for the classification head.
75
+ """
76
+ model_type = "ltgbert"
77
+ def __init__(
78
+ self,
79
+ vocab_size=16384,
80
+ attention_probs_dropout_prob=0.1,
81
+ hidden_dropout_prob=0.1,
82
+ hidden_size=768,
83
+ intermediate_size=2048,
84
+ max_position_embeddings=512,
85
+ position_bucket_size=32,
86
+ num_attention_heads=12,
87
+ num_hidden_layers=12,
88
+ layer_norm_eps=1.0e-7,
89
+ pad_token_id=4,
90
+ output_all_encoded_layers=True,
91
+ classifier_dropout=None,
92
+ **kwargs,
93
+ ):
94
+ super().__init__(pad_token_id=pad_token_id, **kwargs)
95
+
96
+ self.vocab_size = vocab_size
97
+ self.hidden_size = hidden_size
98
+ self.num_hidden_layers = num_hidden_layers
99
+ self.num_attention_heads = num_attention_heads
100
+ self.intermediate_size = intermediate_size
101
+ self.hidden_dropout_prob = hidden_dropout_prob
102
+ self.attention_probs_dropout_prob = attention_probs_dropout_prob
103
+ self.max_position_embeddings = max_position_embeddings
104
+ self.output_all_encoded_layers = output_all_encoded_layers
105
+ self.position_bucket_size = position_bucket_size
106
+ self.layer_norm_eps = layer_norm_eps
107
+ self.classifier_dropout = classifier_dropout
modeling_ltgbert.py ADDED
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1
+ # coding=utf-8
2
+ # Copyright 2023 Language Technology Group from University of Oslo and The HuggingFace Inc. team.
3
+ #
4
+ # Licensed under the Apache License, Version 2.0 (the "License");
5
+ # you may not use this file except in compliance with the License.
6
+ # You may obtain a copy of the License at
7
+ #
8
+ # http://www.apache.org/licenses/LICENSE-2.0
9
+ #
10
+ # Unless required by applicable law or agreed to in writing, software
11
+ # distributed under the License is distributed on an "AS IS" BASIS,
12
+ # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13
+ # See the License for the specific language governing permissions and
14
+ # limitations under the License.
15
+
16
+ """ PyTorch LTG-BERT model."""
17
+
18
+
19
+ import math
20
+ from typing import List, Optional, Tuple, Union
21
+
22
+ import torch
23
+ import torch.nn as nn
24
+ import torch.nn.functional as F
25
+ from torch.utils import checkpoint
26
+
27
+ from .configuration_ltgbert import LtgBertConfig
28
+ from transformers.modeling_utils import PreTrainedModel
29
+ from transformers.activations import gelu_new
30
+ from transformers.modeling_outputs import (
31
+ MaskedLMOutput,
32
+ MultipleChoiceModelOutput,
33
+ QuestionAnsweringModelOutput,
34
+ SequenceClassifierOutput,
35
+ TokenClassifierOutput,
36
+ BaseModelOutput
37
+ )
38
+ from transformers.pytorch_utils import softmax_backward_data
39
+ from transformers.utils import add_start_docstrings, add_start_docstrings_to_model_forward
40
+
41
+
42
+ _CHECKPOINT_FOR_DOC = "ltg/bnc-bert-span"
43
+ _CONFIG_FOR_DOC = "LtgBertConfig"
44
+
45
+
46
+ LTG_BERT_PRETRAINED_MODEL_ARCHIVE_LIST = [
47
+ "bnc-bert-span",
48
+ "bnc-bert-span-2x",
49
+ "bnc-bert-span-0.5x",
50
+ "bnc-bert-span-0.25x",
51
+ "bnc-bert-span-order",
52
+ "bnc-bert-span-document",
53
+ "bnc-bert-span-word",
54
+ "bnc-bert-span-subword",
55
+
56
+ "norbert3-xs",
57
+ "norbert3-small",
58
+ "norbert3-base",
59
+ "norbert3-large",
60
+
61
+ "norbert3-oversampled-base",
62
+ "norbert3-ncc-base",
63
+ "norbert3-nak-base",
64
+ "norbert3-nb-base",
65
+ "norbert3-wiki-base",
66
+ "norbert3-c4-base"
67
+ ]
68
+
69
+
70
+ class Encoder(nn.Module):
71
+ def __init__(self, config, activation_checkpointing=False):
72
+ super().__init__()
73
+ self.layers = nn.ModuleList([EncoderLayer(config) for _ in range(config.num_hidden_layers)])
74
+
75
+ for i, layer in enumerate(self.layers):
76
+ layer.mlp.mlp[1].weight.data *= math.sqrt(1.0 / (2.0 * (1 + i)))
77
+ layer.mlp.mlp[-2].weight.data *= math.sqrt(1.0 / (2.0 * (1 + i)))
78
+
79
+ self.activation_checkpointing = activation_checkpointing
80
+
81
+ def forward(self, hidden_states, attention_mask, relative_embedding):
82
+ hidden_states, attention_probs = [hidden_states], []
83
+
84
+ for layer in self.layers:
85
+ if self.activation_checkpointing:
86
+ hidden_state, attention_p = checkpoint.checkpoint(layer, hidden_states[-1], attention_mask, relative_embedding)
87
+ else:
88
+ hidden_state, attention_p = layer(hidden_states[-1], attention_mask, relative_embedding)
89
+
90
+ hidden_states.append(hidden_state)
91
+ attention_probs.append(attention_p)
92
+
93
+ return hidden_states, attention_probs
94
+
95
+
96
+ class MaskClassifier(nn.Module):
97
+ def __init__(self, config, subword_embedding):
98
+ super().__init__()
99
+ self.nonlinearity = nn.Sequential(
100
+ nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=False),
101
+ nn.Linear(config.hidden_size, config.hidden_size),
102
+ nn.GELU(),
103
+ nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=False),
104
+ nn.Dropout(config.hidden_dropout_prob),
105
+ nn.Linear(subword_embedding.size(1), subword_embedding.size(0))
106
+ )
107
+ self.initialize(config.hidden_size, subword_embedding)
108
+
109
+ def initialize(self, hidden_size, embedding):
110
+ std = math.sqrt(2.0 / (5.0 * hidden_size))
111
+ nn.init.trunc_normal_(self.nonlinearity[1].weight, mean=0.0, std=std, a=-2*std, b=2*std)
112
+ self.nonlinearity[-1].weight = embedding
113
+ self.nonlinearity[1].bias.data.zero_()
114
+ self.nonlinearity[-1].bias.data.zero_()
115
+
116
+ def forward(self, x, masked_lm_labels=None):
117
+ if masked_lm_labels is not None:
118
+ x = torch.index_select(x.flatten(0, 1), 0, torch.nonzero(masked_lm_labels.flatten() != -100).squeeze())
119
+ x = self.nonlinearity(x)
120
+ return x
121
+
122
+
123
+ class EncoderLayer(nn.Module):
124
+ def __init__(self, config):
125
+ super().__init__()
126
+ self.attention = Attention(config)
127
+ self.cross_attention = DummyCrossAttention(config)
128
+ self.mlp = FeedForward(config)
129
+
130
+ def forward(self, x, padding_mask, relative_embedding):
131
+ attention_output, attention_probs = self.attention(x, padding_mask, relative_embedding)
132
+ x = x + attention_output
133
+ x = x + self.cross_attention(x)
134
+ x = x + self.mlp(x)
135
+ return x, attention_probs
136
+
137
+
138
+ class GeGLU(nn.Module):
139
+ def forward(self, x):
140
+ x, gate = x.chunk(2, dim=-1)
141
+ x = x * gelu_new(gate)
142
+ return x
143
+
144
+
145
+ class FeedForward(nn.Module):
146
+ def __init__(self, config):
147
+ super().__init__()
148
+ self.mlp = nn.Sequential(
149
+ nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps, elementwise_affine=False),
150
+ nn.Linear(config.hidden_size, 2*config.intermediate_size, bias=False),
151
+ GeGLU(),
152
+ nn.LayerNorm(config.intermediate_size, eps=config.layer_norm_eps, elementwise_affine=False),
153
+ nn.Linear(config.intermediate_size, config.hidden_size, bias=False),
154
+ nn.Dropout(config.hidden_dropout_prob)
155
+ )
156
+ self.initialize(config.hidden_size)
157
+
158
+ def initialize(self, hidden_size):
159
+ std = math.sqrt(2.0 / (5.0 * hidden_size))
160
+ nn.init.trunc_normal_(self.mlp[1].weight, mean=0.0, std=std, a=-2*std, b=2*std)
161
+ nn.init.trunc_normal_(self.mlp[-2].weight, mean=0.0, std=std, a=-2*std, b=2*std)
162
+
163
+ def forward(self, x):
164
+ return self.mlp(x)
165
+
166
+
167
+ class MaskedSoftmax(torch.autograd.Function):
168
+ @staticmethod
169
+ def forward(self, x, mask, dim):
170
+ self.dim = dim
171
+ x.masked_fill_(mask, float('-inf'))
172
+ x = torch.softmax(x, self.dim)
173
+ x.masked_fill_(mask, 0.0)
174
+ self.save_for_backward(x)
175
+ return x
176
+
177
+ @staticmethod
178
+ def backward(self, grad_output):
179
+ output, = self.saved_tensors
180
+ input_grad = softmax_backward_data(self, grad_output, output, self.dim, output)
181
+ return input_grad, None, None
182
+
183
+
184
+ class Attention(nn.Module):
185
+ def __init__(self, config):
186
+ super().__init__()
187
+
188
+ self.config = config
189
+
190
+ if config.hidden_size % config.num_attention_heads != 0:
191
+ raise ValueError(f"The hidden size {config.hidden_size} is not a multiple of the number of attention heads {config.num_attention_heads}")
192
+
193
+ self.hidden_size = config.hidden_size
194
+ self.num_heads = config.num_attention_heads
195
+ self.head_size = config.hidden_size // config.num_attention_heads
196
+
197
+ self.in_proj_qk = nn.Linear(config.hidden_size, 2*config.hidden_size, bias=True)
198
+ self.in_proj_v = nn.Linear(config.hidden_size, config.hidden_size, bias=True)
199
+ self.out_proj = nn.Linear(config.hidden_size, config.hidden_size, bias=True)
200
+
201
+ self.pre_layer_norm = nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=False)
202
+ self.post_layer_norm = nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=True)
203
+
204
+ position_indices = torch.arange(config.max_position_embeddings, dtype=torch.long).unsqueeze(1) \
205
+ - torch.arange(config.max_position_embeddings, dtype=torch.long).unsqueeze(0)
206
+ position_indices = self.make_log_bucket_position(position_indices, config.position_bucket_size, config.max_position_embeddings)
207
+ position_indices = config.position_bucket_size - 1 + position_indices
208
+ self.register_buffer("position_indices", position_indices, persistent=True)
209
+
210
+ self.dropout = nn.Dropout(config.attention_probs_dropout_prob)
211
+ self.scale = 1.0 / math.sqrt(3 * self.head_size)
212
+ self.initialize()
213
+
214
+ def make_log_bucket_position(self, relative_pos, bucket_size, max_position):
215
+ sign = torch.sign(relative_pos)
216
+ mid = bucket_size // 2
217
+ abs_pos = torch.where((relative_pos < mid) & (relative_pos > -mid), mid - 1, torch.abs(relative_pos).clamp(max=max_position - 1))
218
+ log_pos = torch.ceil(torch.log(abs_pos / mid) / math.log((max_position-1) / mid) * (mid - 1)).int() + mid
219
+ bucket_pos = torch.where(abs_pos <= mid, relative_pos, log_pos * sign).long()
220
+ return bucket_pos
221
+
222
+ def initialize(self):
223
+ std = math.sqrt(2.0 / (5.0 * self.hidden_size))
224
+ nn.init.trunc_normal_(self.in_proj_qk.weight, mean=0.0, std=std, a=-2*std, b=2*std)
225
+ nn.init.trunc_normal_(self.in_proj_v.weight, mean=0.0, std=std, a=-2*std, b=2*std)
226
+ nn.init.trunc_normal_(self.out_proj.weight, mean=0.0, std=std, a=-2*std, b=2*std)
227
+ self.in_proj_qk.bias.data.zero_()
228
+ self.in_proj_v.bias.data.zero_()
229
+ self.out_proj.bias.data.zero_()
230
+
231
+ def compute_attention_scores(self, hidden_states, relative_embedding):
232
+ key_len, batch_size, _ = hidden_states.size()
233
+ query_len = key_len
234
+
235
+ if self.position_indices.size(0) < query_len:
236
+ position_indices = torch.arange(query_len, dtype=torch.long).unsqueeze(1) \
237
+ - torch.arange(query_len, dtype=torch.long).unsqueeze(0)
238
+ position_indices = self.make_log_bucket_position(position_indices, self.position_bucket_size, 512)
239
+ position_indices = self.position_bucket_size - 1 + position_indices
240
+ self.position_indices = position_indices.to(hidden_states.device)
241
+
242
+ hidden_states = self.pre_layer_norm(hidden_states)
243
+
244
+ query, key = self.in_proj_qk(hidden_states).chunk(2, dim=2) # shape: [T, B, D]
245
+ value = self.in_proj_v(hidden_states) # shape: [T, B, D]
246
+
247
+ query = query.reshape(query_len, batch_size * self.num_heads, self.head_size).transpose(0, 1)
248
+ key = key.reshape(key_len, batch_size * self.num_heads, self.head_size).transpose(0, 1)
249
+ value = value.view(key_len, batch_size * self.num_heads, self.head_size).transpose(0, 1)
250
+
251
+ attention_scores = torch.bmm(query, key.transpose(1, 2) * self.scale)
252
+
253
+ query_pos, key_pos = self.in_proj_qk(self.dropout(relative_embedding)).chunk(2, dim=-1) # shape: [2T-1, D]
254
+ query_pos = query_pos.view(-1, self.num_heads, self.head_size) # shape: [2T-1, H, D]
255
+ key_pos = key_pos.view(-1, self.num_heads, self.head_size) # shape: [2T-1, H, D]
256
+
257
+ query = query.view(batch_size, self.num_heads, query_len, self.head_size)
258
+ key = key.view(batch_size, self.num_heads, query_len, self.head_size)
259
+
260
+ attention_c_p = torch.einsum("bhqd,khd->bhqk", query, key_pos.squeeze(1) * self.scale)
261
+ attention_p_c = torch.einsum("bhkd,qhd->bhqk", key * self.scale, query_pos.squeeze(1))
262
+
263
+ position_indices = self.position_indices[:query_len, :key_len].expand(batch_size, self.num_heads, -1, -1)
264
+ attention_c_p = attention_c_p.gather(3, position_indices)
265
+ attention_p_c = attention_p_c.gather(2, position_indices)
266
+
267
+ attention_scores = attention_scores.view(batch_size, self.num_heads, query_len, key_len)
268
+ attention_scores.add_(attention_c_p)
269
+ attention_scores.add_(attention_p_c)
270
+
271
+ return attention_scores, value
272
+
273
+ def compute_output(self, attention_probs, value):
274
+ attention_probs = self.dropout(attention_probs)
275
+ context = torch.bmm(attention_probs.flatten(0, 1), value) # shape: [B*H, Q, D]
276
+ context = context.transpose(0, 1).reshape(context.size(1), -1, self.hidden_size) # shape: [Q, B, H*D]
277
+ context = self.out_proj(context)
278
+ context = self.post_layer_norm(context)
279
+ context = self.dropout(context)
280
+ return context
281
+
282
+ def forward(self, hidden_states, attention_mask, relative_embedding):
283
+ attention_scores, value = self.compute_attention_scores(hidden_states, relative_embedding)
284
+ attention_probs = MaskedSoftmax.apply(attention_scores, attention_mask, -1)
285
+ return self.compute_output(attention_probs, value), attention_probs.detach()
286
+
287
+
288
+ class DummyCrossAttention(nn.Module):
289
+ def __init__(self, config):
290
+ super().__init__()
291
+
292
+ self.config = config
293
+ self.hidden_size = config.hidden_size
294
+
295
+ self.amputed_linear = nn.Linear(config.hidden_size, config.hidden_size, bias=True)
296
+
297
+ self.pre_layer_norm = nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=False)
298
+ self.post_layer_norm = nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=True)
299
+
300
+ self.dropout = nn.Dropout(config.attention_probs_dropout_prob)
301
+ self.initialize()
302
+
303
+ def initialize(self):
304
+ std = math.sqrt(2.0 / (5.0 * self.hidden_size))
305
+ nn.init.trunc_normal_(self.amputed_linear.weight, mean=0.0, std=std, a=-2*std, b=2*std)
306
+ nn.init.zeros_(self.amputed_linear.bias)
307
+
308
+ def forward(self, q, *args, **kwargs):
309
+ q = self.pre_layer_norm(q)
310
+ q = self.amputed_linear(q)
311
+ q = self.post_layer_norm(q)
312
+ q = self.dropout(q)
313
+ return q
314
+
315
+
316
+ class Embedding(nn.Module):
317
+ def __init__(self, config):
318
+ super().__init__()
319
+ self.hidden_size = config.hidden_size
320
+
321
+ self.word_embedding = nn.Embedding(config.vocab_size, config.hidden_size)
322
+ self.word_layer_norm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps, elementwise_affine=False)
323
+ self.dropout = nn.Dropout(config.hidden_dropout_prob)
324
+
325
+ self.relative_embedding = nn.Parameter(torch.empty(2 * config.position_bucket_size - 1, config.hidden_size))
326
+ self.relative_layer_norm = nn.LayerNorm(config.hidden_size, eps=config.layer_norm_eps)
327
+
328
+ self.initialize()
329
+
330
+ def initialize(self):
331
+ std = math.sqrt(2.0 / (5.0 * self.hidden_size))
332
+ nn.init.trunc_normal_(self.relative_embedding, mean=0.0, std=std, a=-2*std, b=2*std)
333
+ nn.init.trunc_normal_(self.word_embedding.weight, mean=0.0, std=std, a=-2*std, b=2*std)
334
+
335
+ def forward(self, input_ids):
336
+ word_embedding = self.dropout(self.word_layer_norm(self.word_embedding(input_ids)))
337
+ relative_embeddings = self.relative_layer_norm(self.relative_embedding)
338
+ return word_embedding, relative_embeddings
339
+
340
+
341
+ #
342
+ # HuggingFace wrappers
343
+ #
344
+
345
+ class LtgBertPreTrainedModel(PreTrainedModel):
346
+ """
347
+ An abstract class to handle weights initialization and a simple interface for downloading and loading pretrained
348
+ models.
349
+ """
350
+
351
+ config_class = LtgBertConfig
352
+ base_model_prefix = "bnc-bert"
353
+ supports_gradient_checkpointing = True
354
+
355
+ def _set_gradient_checkpointing(self, module, value=False):
356
+ if isinstance(module, Encoder):
357
+ module.activation_checkpointing = value
358
+
359
+ def _init_weights(self, _):
360
+ pass # everything is already initialized
361
+
362
+
363
+ LTG_BERT_START_DOCSTRING = r"""
364
+ This model inherits from [`PreTrainedModel`]. Check the superclass documentation for the generic methods the
365
+ library implements for all its model (such as downloading or saving, resizing the input embeddings, pruning heads
366
+ etc.)
367
+ This model is also a PyTorch [torch.nn.Module](https://pytorch.org/docs/stable/nn.html#torch.nn.Module) subclass.
368
+ Use it as a regular PyTorch Module and refer to the PyTorch documentation for all matter related to general usage
369
+ and behavior.
370
+ Parameters:
371
+ config ([`LtgBertConfig`]): Model configuration class with all the parameters of the model.
372
+ Initializing with a config file does not load the weights associated with the model, only the
373
+ configuration. Check out the [`~PreTrainedModel.from_pretrained`] method to load the model weights.
374
+ """
375
+
376
+ LTG_BERT_INPUTS_DOCSTRING = r"""
377
+ Args:
378
+ input_ids (`torch.LongTensor` of shape `({0})`):
379
+ Indices of input sequence tokens in the vocabulary.
380
+ Indices can be obtained using [`AutoTokenizer`]. See [`PreTrainedTokenizer.encode`] and
381
+ [`PreTrainedTokenizer.__call__`] for details.
382
+ [What are input IDs?](../glossary#input-ids)
383
+ attention_mask (`torch.FloatTensor` of shape `({0})`, *optional*):
384
+ Mask to avoid performing attention on padding token indices. Mask values selected in `[0, 1]`:
385
+ - 1 for tokens that are **not masked**,
386
+ - 0 for tokens that are **masked**.
387
+ [What are attention masks?](../glossary#attention-mask)
388
+ output_hidden_states (`bool`, *optional*):
389
+ Whether or not to return the hidden states of all layers. See `hidden_states` under returned tensors for
390
+ more detail.
391
+ output_attentions (`bool`, *optional*):
392
+ Whether or not to return the attentions tensors of all attention layers. See `attentions` under returned
393
+ tensors for more detail.
394
+ return_dict (`bool`, *optional*):
395
+ Whether or not to return a [`~utils.ModelOutput`] instead of a plain tuple.
396
+ """
397
+
398
+
399
+ @add_start_docstrings(
400
+ "The bare LTG-BERT transformer outputting raw hidden-states without any specific head on top.",
401
+ LTG_BERT_START_DOCSTRING,
402
+ )
403
+ class LtgBertModel(LtgBertPreTrainedModel):
404
+ def __init__(self, config, add_mlm_layer=False):
405
+ super().__init__(config)
406
+ self.config = config
407
+
408
+ self.embedding = Embedding(config)
409
+ self.transformer = Encoder(config, activation_checkpointing=False)
410
+ self.classifier = MaskClassifier(config, self.embedding.word_embedding.weight) if add_mlm_layer else None
411
+
412
+ def get_input_embeddings(self):
413
+ return self.embedding.word_embedding
414
+
415
+ def set_input_embeddings(self, value):
416
+ self.embedding.word_embedding = value
417
+
418
+ def get_contextualized_embeddings(
419
+ self,
420
+ input_ids: Optional[torch.Tensor] = None,
421
+ attention_mask: Optional[torch.Tensor] = None
422
+ ) -> List[torch.Tensor]:
423
+ if input_ids is not None:
424
+ input_shape = input_ids.size()
425
+ else:
426
+ raise ValueError("You have to specify input_ids")
427
+
428
+ batch_size, seq_length = input_shape
429
+ device = input_ids.device
430
+
431
+ if attention_mask is None:
432
+ attention_mask = torch.zeros(batch_size, seq_length, dtype=torch.bool, device=device)
433
+ else:
434
+ attention_mask = ~attention_mask.bool()
435
+ attention_mask = attention_mask.unsqueeze(1).unsqueeze(2)
436
+
437
+ static_embeddings, relative_embedding = self.embedding(input_ids.t())
438
+ contextualized_embeddings, attention_probs = self.transformer(static_embeddings, attention_mask, relative_embedding)
439
+ contextualized_embeddings = [e.transpose(0, 1) for e in contextualized_embeddings]
440
+ last_layer = contextualized_embeddings[-1]
441
+ contextualized_embeddings = [contextualized_embeddings[0]] + [
442
+ contextualized_embeddings[i] - contextualized_embeddings[i - 1]
443
+ for i in range(1, len(contextualized_embeddings))
444
+ ]
445
+ return last_layer, contextualized_embeddings, attention_probs
446
+
447
+ @add_start_docstrings_to_model_forward(LTG_BERT_INPUTS_DOCSTRING.format("batch_size, sequence_length"))
448
+ def forward(
449
+ self,
450
+ input_ids: Optional[torch.Tensor] = None,
451
+ attention_mask: Optional[torch.Tensor] = None,
452
+ output_hidden_states: Optional[bool] = None,
453
+ output_attentions: Optional[bool] = None,
454
+ return_dict: Optional[bool] = None,
455
+ ) -> Union[Tuple[torch.Tensor], BaseModelOutput]:
456
+
457
+ output_attentions = output_attentions if output_attentions is not None else self.config.output_attentions
458
+ output_hidden_states = (
459
+ output_hidden_states if output_hidden_states is not None else self.config.output_hidden_states
460
+ )
461
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
462
+
463
+ sequence_output, contextualized_embeddings, attention_probs = self.get_contextualized_embeddings(input_ids, attention_mask)
464
+
465
+ if not return_dict:
466
+ return (
467
+ sequence_output,
468
+ *([contextualized_embeddings] if output_hidden_states else []),
469
+ *([attention_probs] if output_attentions else [])
470
+ )
471
+
472
+ return BaseModelOutput(
473
+ last_hidden_state=sequence_output,
474
+ hidden_states=contextualized_embeddings if output_hidden_states else None,
475
+ attentions=attention_probs if output_attentions else None
476
+ )
477
+
478
+
479
+ @add_start_docstrings("""LTG-BERT model with a `language modeling` head on top.""", LTG_BERT_START_DOCSTRING)
480
+ class LtgBertForMaskedLM(LtgBertModel):
481
+ _keys_to_ignore_on_load_unexpected = ["head"]
482
+
483
+ def __init__(self, config):
484
+ super().__init__(config, add_mlm_layer=True)
485
+
486
+ def get_output_embeddings(self):
487
+ return self.classifier.nonlinearity[-1].weight
488
+
489
+ def set_output_embeddings(self, new_embeddings):
490
+ self.classifier.nonlinearity[-1].weight = new_embeddings
491
+
492
+ @add_start_docstrings_to_model_forward(LTG_BERT_INPUTS_DOCSTRING.format("batch_size, sequence_length"))
493
+ def forward(
494
+ self,
495
+ input_ids: Optional[torch.Tensor] = None,
496
+ attention_mask: Optional[torch.Tensor] = None,
497
+ output_hidden_states: Optional[bool] = None,
498
+ output_attentions: Optional[bool] = None,
499
+ return_dict: Optional[bool] = None,
500
+ labels: Optional[torch.LongTensor] = None,
501
+ ) -> Union[Tuple[torch.Tensor], MaskedLMOutput]:
502
+ r"""
503
+ labels (`torch.LongTensor` of shape `(batch_size, sequence_length)`, *optional*):
504
+ Labels for computing the masked language modeling loss. Indices should be in `[-100, 0, ...,
505
+ config.vocab_size]` (see `input_ids` docstring) Tokens with indices set to `-100` are ignored (masked), the
506
+ loss is only computed for the tokens with labels in `[0, ..., config.vocab_size]`
507
+ """
508
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
509
+
510
+ sequence_output, contextualized_embeddings, attention_probs = self.get_contextualized_embeddings(input_ids, attention_mask)
511
+ subword_prediction = self.classifier(sequence_output)
512
+
513
+ masked_lm_loss = None
514
+ if labels is not None:
515
+ masked_lm_loss = F.cross_entropy(subword_prediction.flatten(0, 1), labels.flatten())
516
+
517
+ if not return_dict:
518
+ output = (
519
+ subword_prediction,
520
+ *([contextualized_embeddings] if output_hidden_states else []),
521
+ *([attention_probs] if output_attentions else [])
522
+ )
523
+ return ((masked_lm_loss,) + output) if masked_lm_loss is not None else output
524
+
525
+ return MaskedLMOutput(
526
+ loss=masked_lm_loss,
527
+ logits=subword_prediction,
528
+ hidden_states=contextualized_embeddings if output_hidden_states else None,
529
+ attentions=attention_probs if output_attentions else None
530
+ )
531
+
532
+
533
+ class Classifier(nn.Module):
534
+ def __init__(self, config, num_labels: int):
535
+ super().__init__()
536
+
537
+ drop_out = getattr(config, "classifier_dropout", config.hidden_dropout_prob)
538
+
539
+ self.nonlinearity = nn.Sequential(
540
+ nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=False),
541
+ nn.Linear(config.hidden_size, config.hidden_size),
542
+ nn.GELU(),
543
+ nn.LayerNorm(config.hidden_size, config.layer_norm_eps, elementwise_affine=False),
544
+ nn.Dropout(drop_out),
545
+ nn.Linear(config.hidden_size, num_labels)
546
+ )
547
+ self.initialize(config.hidden_size)
548
+
549
+ def initialize(self, hidden_size):
550
+ std = math.sqrt(2.0 / (5.0 * hidden_size))
551
+ nn.init.trunc_normal_(self.nonlinearity[1].weight, mean=0.0, std=std, a=-2*std, b=2*std)
552
+ nn.init.trunc_normal_(self.nonlinearity[-1].weight, mean=0.0, std=std, a=-2*std, b=2*std)
553
+ self.nonlinearity[1].bias.data.zero_()
554
+ self.nonlinearity[-1].bias.data.zero_()
555
+
556
+ def forward(self, x):
557
+ x = self.nonlinearity(x)
558
+ return x
559
+
560
+
561
+ @add_start_docstrings(
562
+ """
563
+ LTG-BERT model with a sequence classification/regression head on top (a linear layer on top of the pooled
564
+ output) e.g. for GLUE tasks.
565
+ """,
566
+ LTG_BERT_START_DOCSTRING,
567
+ )
568
+ class LtgBertForSequenceClassification(LtgBertModel):
569
+ _keys_to_ignore_on_load_unexpected = ["classifier"]
570
+ _keys_to_ignore_on_load_missing = ["head"]
571
+
572
+ def __init__(self, config):
573
+ super().__init__(config, add_mlm_layer=False)
574
+
575
+ self.num_labels = config.num_labels
576
+ self.head = Classifier(config, self.num_labels)
577
+
578
+ @add_start_docstrings_to_model_forward(LTG_BERT_INPUTS_DOCSTRING.format("batch_size, sequence_length"))
579
+ def forward(
580
+ self,
581
+ input_ids: Optional[torch.Tensor] = None,
582
+ attention_mask: Optional[torch.Tensor] = None,
583
+ output_attentions: Optional[bool] = None,
584
+ output_hidden_states: Optional[bool] = None,
585
+ return_dict: Optional[bool] = None,
586
+ labels: Optional[torch.LongTensor] = None,
587
+ ) -> Union[Tuple[torch.Tensor], SequenceClassifierOutput]:
588
+ r"""
589
+ labels (`torch.LongTensor` of shape `(batch_size,)`, *optional*):
590
+ Labels for computing the sequence classification/regression loss. Indices should be in `[0, ...,
591
+ config.num_labels - 1]`. If `config.num_labels == 1` a regression loss is computed (Mean-Square loss), If
592
+ `config.num_labels > 1` a classification loss is computed (Cross-Entropy).
593
+ """
594
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
595
+
596
+ sequence_output, contextualized_embeddings, attention_probs = self.get_contextualized_embeddings(input_ids, attention_mask)
597
+ logits = self.head(sequence_output[:, 0, :])
598
+
599
+ loss = None
600
+ if labels is not None:
601
+ if self.config.problem_type is None:
602
+ if self.num_labels == 1:
603
+ self.config.problem_type = "regression"
604
+ elif self.num_labels > 1 and (labels.dtype == torch.long or labels.dtype == torch.int):
605
+ self.config.problem_type = "single_label_classification"
606
+ else:
607
+ self.config.problem_type = "multi_label_classification"
608
+
609
+ if self.config.problem_type == "regression":
610
+ loss_fct = nn.MSELoss()
611
+ if self.num_labels == 1:
612
+ loss = loss_fct(logits.squeeze(), labels.squeeze())
613
+ else:
614
+ loss = loss_fct(logits, labels)
615
+ elif self.config.problem_type == "single_label_classification":
616
+ loss_fct = nn.CrossEntropyLoss()
617
+ loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1))
618
+ elif self.config.problem_type == "multi_label_classification":
619
+ loss_fct = nn.BCEWithLogitsLoss()
620
+ loss = loss_fct(logits, labels)
621
+
622
+ if not return_dict:
623
+ output = (
624
+ logits,
625
+ *([contextualized_embeddings] if output_hidden_states else []),
626
+ *([attention_probs] if output_attentions else [])
627
+ )
628
+ return ((loss,) + output) if loss is not None else output
629
+
630
+ return SequenceClassifierOutput(
631
+ loss=loss,
632
+ logits=logits,
633
+ hidden_states=contextualized_embeddings if output_hidden_states else None,
634
+ attentions=attention_probs if output_attentions else None
635
+ )
636
+
637
+
638
+ @add_start_docstrings(
639
+ """
640
+ LTG-BERT model with a token classification head on top (a linear layer on top of the hidden-states output) e.g. for
641
+ Named-Entity-Recognition (NER) tasks.
642
+ """,
643
+ LTG_BERT_START_DOCSTRING,
644
+ )
645
+ class LtgBertForTokenClassification(LtgBertModel):
646
+ _keys_to_ignore_on_load_unexpected = ["classifier"]
647
+ _keys_to_ignore_on_load_missing = ["head"]
648
+
649
+ def __init__(self, config):
650
+ super().__init__(config, add_mlm_layer=False)
651
+
652
+ self.num_labels = config.num_labels
653
+ self.head = Classifier(config, self.num_labels)
654
+
655
+ @add_start_docstrings_to_model_forward(LTG_BERT_INPUTS_DOCSTRING.format("batch_size, sequence_length"))
656
+ def forward(
657
+ self,
658
+ input_ids: Optional[torch.Tensor] = None,
659
+ attention_mask: Optional[torch.Tensor] = None,
660
+ token_type_ids: Optional[torch.Tensor] = None,
661
+ position_ids: Optional[torch.Tensor] = None,
662
+ output_attentions: Optional[bool] = None,
663
+ output_hidden_states: Optional[bool] = None,
664
+ return_dict: Optional[bool] = None,
665
+ labels: Optional[torch.LongTensor] = None,
666
+ ) -> Union[Tuple[torch.Tensor], TokenClassifierOutput]:
667
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
668
+
669
+ sequence_output, contextualized_embeddings, attention_probs = self.get_contextualized_embeddings(input_ids, attention_mask)
670
+ logits = self.head(sequence_output)
671
+
672
+ loss = None
673
+ if labels is not None:
674
+ loss_fct = nn.CrossEntropyLoss()
675
+ loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1))
676
+
677
+ if not return_dict:
678
+ output = (
679
+ logits,
680
+ *([contextualized_embeddings] if output_hidden_states else []),
681
+ *([attention_probs] if output_attentions else [])
682
+ )
683
+ return ((loss,) + output) if loss is not None else output
684
+
685
+ return TokenClassifierOutput(
686
+ loss=loss,
687
+ logits=logits,
688
+ hidden_states=contextualized_embeddings if output_hidden_states else None,
689
+ attentions=attention_probs if output_attentions else None
690
+ )
691
+
692
+
693
+ @add_start_docstrings(
694
+ """
695
+ LTG-BERT model with a span classification head on top for extractive question-answering tasks like SQuAD (a linear
696
+ layers on top of the hidden-states output to compute `span start logits` and `span end logits`).
697
+ """,
698
+ LTG_BERT_START_DOCSTRING,
699
+ )
700
+ class LtgBertForQuestionAnswering(LtgBertModel):
701
+ _keys_to_ignore_on_load_unexpected = ["classifier"]
702
+ _keys_to_ignore_on_load_missing = ["head"]
703
+
704
+ def __init__(self, config):
705
+ super().__init__(config, add_mlm_layer=False)
706
+
707
+ self.num_labels = config.num_labels
708
+ self.head = Classifier(config, self.num_labels)
709
+
710
+ @add_start_docstrings_to_model_forward(LTG_BERT_INPUTS_DOCSTRING.format("batch_size, sequence_length"))
711
+ def forward(
712
+ self,
713
+ input_ids: Optional[torch.Tensor] = None,
714
+ attention_mask: Optional[torch.Tensor] = None,
715
+ token_type_ids: Optional[torch.Tensor] = None,
716
+ position_ids: Optional[torch.Tensor] = None,
717
+ output_attentions: Optional[bool] = None,
718
+ output_hidden_states: Optional[bool] = None,
719
+ return_dict: Optional[bool] = None,
720
+ start_positions: Optional[torch.Tensor] = None,
721
+ end_positions: Optional[torch.Tensor] = None
722
+ ) -> Union[Tuple[torch.Tensor], QuestionAnsweringModelOutput]:
723
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
724
+
725
+ sequence_output, contextualized_embeddings, attention_probs = self.get_contextualized_embeddings(input_ids, attention_mask)
726
+ logits = self.head(sequence_output)
727
+
728
+ start_logits, end_logits = logits.split(1, dim=-1)
729
+ start_logits = start_logits.squeeze(-1).contiguous()
730
+ end_logits = end_logits.squeeze(-1).contiguous()
731
+
732
+ total_loss = None
733
+ if start_positions is not None and end_positions is not None:
734
+ # If we are on multi-GPU, split add a dimension
735
+ if len(start_positions.size()) > 1:
736
+ start_positions = start_positions.squeeze(-1)
737
+ if len(end_positions.size()) > 1:
738
+ end_positions = end_positions.squeeze(-1)
739
+
740
+ # sometimes the start/end positions are outside our model inputs, we ignore these terms
741
+ ignored_index = start_logits.size(1)
742
+ start_positions = start_positions.clamp(0, ignored_index)
743
+ end_positions = end_positions.clamp(0, ignored_index)
744
+
745
+ loss_fct = nn.CrossEntropyLoss(ignore_index=ignored_index)
746
+ start_loss = loss_fct(start_logits, start_positions)
747
+ end_loss = loss_fct(end_logits, end_positions)
748
+ total_loss = (start_loss + end_loss) / 2
749
+
750
+ if not return_dict:
751
+ output = (
752
+ start_logits,
753
+ end_logits,
754
+ *([contextualized_embeddings] if output_hidden_states else []),
755
+ *([attention_probs] if output_attentions else [])
756
+ )
757
+ return ((total_loss,) + output) if total_loss is not None else output
758
+
759
+ return QuestionAnsweringModelOutput(
760
+ loss=total_loss,
761
+ start_logits=start_logits,
762
+ end_logits=end_logits,
763
+ hidden_states=contextualized_embeddings if output_hidden_states else None,
764
+ attentions=attention_probs if output_attentions else None
765
+ )
766
+
767
+
768
+ @add_start_docstrings(
769
+ """
770
+ LTG-BERT model with a multiple choice classification head on top (a linear layer on top of the pooled output and a
771
+ softmax) e.g. for RocStories/SWAG tasks.
772
+ """,
773
+ LTG_BERT_START_DOCSTRING,
774
+ )
775
+ class LtgBertForMultipleChoice(LtgBertModel):
776
+ _keys_to_ignore_on_load_unexpected = ["classifier"]
777
+ _keys_to_ignore_on_load_missing = ["head"]
778
+
779
+ def __init__(self, config):
780
+ super().__init__(config, add_mlm_layer=False)
781
+
782
+ self.num_labels = getattr(config, "num_labels", 2)
783
+ self.head = Classifier(config, self.num_labels)
784
+
785
+ @add_start_docstrings_to_model_forward(LTG_BERT_INPUTS_DOCSTRING.format("batch_size, num_choices, sequence_length"))
786
+ def forward(
787
+ self,
788
+ input_ids: Optional[torch.Tensor] = None,
789
+ attention_mask: Optional[torch.Tensor] = None,
790
+ token_type_ids: Optional[torch.Tensor] = None,
791
+ position_ids: Optional[torch.Tensor] = None,
792
+ labels: Optional[torch.Tensor] = None,
793
+ output_attentions: Optional[bool] = None,
794
+ output_hidden_states: Optional[bool] = None,
795
+ return_dict: Optional[bool] = None
796
+ ) -> Union[Tuple[torch.Tensor], MultipleChoiceModelOutput]:
797
+ return_dict = return_dict if return_dict is not None else self.config.use_return_dict
798
+ num_choices = input_ids.shape[1]
799
+
800
+ flat_input_ids = input_ids.view(-1, input_ids.size(-1))
801
+ flat_attention_mask = attention_mask.view(-1, attention_mask.size(-1)) if attention_mask is not None else None
802
+
803
+ sequence_output, contextualized_embeddings, attention_probs = self.get_contextualized_embeddings(flat_input_ids, flat_attention_mask)
804
+ logits = self.head(sequence_output)
805
+ reshaped_logits = logits.view(-1, num_choices)
806
+
807
+ loss = None
808
+ if labels is not None:
809
+ loss_fct = nn.CrossEntropyLoss()
810
+ loss = loss_fct(reshaped_logits, labels)
811
+
812
+ if not return_dict:
813
+ output = (
814
+ reshaped_logits,
815
+ *([contextualized_embeddings] if output_hidden_states else []),
816
+ *([attention_probs] if output_attentions else [])
817
+ )
818
+ return ((loss,) + output) if loss is not None else output
819
+
820
+ return MultipleChoiceModelOutput(
821
+ loss=loss,
822
+ logits=reshaped_logits,
823
+ hidden_states=contextualized_embeddings if output_hidden_states else None,
824
+ attentions=attention_probs if output_attentions else None
825
+ )
pytorch_model.bin ADDED
@@ -0,0 +1,3 @@
 
 
 
 
1
+ version https://git-lfs.github.com/spec/v1
2
+ oid sha256:4a7e4d017691fffc6ff2c47654cc665f8a00a31494a23894e1e254274d179ca4
3
+ size 811748865
special_tokens_map.json ADDED
@@ -0,0 +1,9 @@
 
 
 
 
 
 
 
 
 
 
1
+ {
2
+ "bos_token": "[BOS]",
3
+ "cls_token": "[CLS]",
4
+ "eos_token": "[EOS]",
5
+ "mask_token": "[MASK]",
6
+ "pad_token": "[PAD]",
7
+ "sep_token": "[SEP]",
8
+ "unk_token": "[UNK]"
9
+ }
tokenizer.json ADDED
The diff for this file is too large to render. See raw diff
 
tokenizer_config.json ADDED
@@ -0,0 +1,4 @@
 
 
 
 
 
1
+ {
2
+ "model_max_length": 1000000000000000019884624838656,
3
+ "tokenizer_class": "PreTrainedTokenizerFast"
4
+ }