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from torch import nn |
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from transformers import BertModel |
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import logging |
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from transformers.modeling_outputs import TokenClassifierOutput |
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class BertClassifier(nn.Module): |
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def __init__(self, bert_model="Sifal/dzarabert", num_labels=2, dropout=0.1): |
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super().__init__() |
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self.bert = BertModel.from_pretrained(bert_model) |
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self.num_labels = num_labels |
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self.classifier = nn.Sequential( |
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nn.Linear(self.bert.config.hidden_size, self.bert.config.hidden_size), |
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nn.ReLU(), |
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nn.Dropout(dropout), |
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nn.Linear(self.bert.config.hidden_size, num_labels)) |
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def forward(self, input_ids=None, attention_mask=None,labels=None): |
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output = self.bert(input_ids, attention_mask=attention_mask) |
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logits = self.classifier(output.pooler_output) |
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loss = None |
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if labels is not None: |
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loss_fct = nn.CrossEntropyLoss() |
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loss = loss_fct(logits.view(-1, self.num_labels), labels.view(-1)) |
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return TokenClassifierOutput(loss=loss, logits=logits, hidden_states=output.hidden_states,attentions=output.attentions) |
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