Trying to use text classifier model shared by https://github.com/allenai/scibert/blob/master/scibert/models/text_classifier.py
Everything used to work and suddenly I keep getting this error: Cannot register text_classifier as Model; name already in use for TextClassifier
What might be the reason? any suggestion?
from typing import Dict, Optional, List, Any
import torch
import torch.nn.functional as F
from allennlp.data import Vocabulary
from allennlp.models.model import Model
from allennlp.modules import FeedForward, TextFieldEmbedder, Seq2SeqEncoder
from allennlp.nn import InitializerApplicator, RegularizerApplicator
from allennlp.nn import util
from allennlp.training.metrics import CategoricalAccuracy, F1Measure
from overrides import overrides
@Model.register("text_classifier")
class TextClassifier(Model):
"""
Implements a basic text classifier:
1) Embed tokens using `text_field_embedder`
2) Seq2SeqEncoder, e.g. BiLSTM
3) Append the first and last encoder states
4) Final feedforward layer
Optimized with CrossEntropyLoss. Evaluated with CategoricalAccuracy & F1.
"""
def __init__(self, vocab: Vocabulary,
text_field_embedder: TextFieldEmbedder,
text_encoder: Seq2SeqEncoder,
classifier_feedforward: FeedForward,
verbose_metrics: False,
initializer: InitializerApplicator = InitializerApplicator(),
regularizer: Optional[RegularizerApplicator] = None,
) -> None:
super(TextClassifier, self).__init__(vocab, regularizer)
self.text_field_embedder = text_field_embedder
self.num_classes = self.vocab.get_vocab_size("labels")
self.text_encoder = text_encoder
self.classifier_feedforward = classifier_feedforward
self.prediction_layer = torch.nn.Linear(self.classifier_feedforward.get_output_dim() , self.num_classes)
self.label_accuracy = CategoricalAccuracy()
self.label_f1_metrics = {}
self.verbose_metrics = verbose_metrics
for i in range(self.num_classes):
self.label_f1_metrics[vocab.get_token_from_index(index=i, namespace="labels")] = F1Measure(positive_label=i)
self.loss = torch.nn.CrossEntropyLoss()
self.pool = lambda text, mask: util.get_final_encoder_states(text, mask, bidirectional=True)
initializer(self)
@overrides
def forward(self,
text: Dict[str, torch.LongTensor],
label: torch.IntTensor = None,
metadata: List[Dict[str, Any]] = None) -> Dict[str, torch.Tensor]:
"""
Parameters
----------
text : Dict[str, torch.LongTensor]
From a ``TextField``
label : torch.IntTensor, optional (default = None)
From a ``LabelField``
metadata : ``List[Dict[str, Any]]``, optional, (default = None)
Metadata containing the original tokenization of the premise and
hypothesis with 'premise_tokens' and 'hypothesis_tokens' keys respectively.
Returns
-------
An output dictionary consisting of:
label_logits : torch.FloatTensor
A tensor of shape ``(batch_size, num_labels)`` representing unnormalised log probabilities of the label.
label_probs : torch.FloatTensor
A tensor of shape ``(batch_size, num_labels)`` representing probabilities of the label.
loss : torch.FloatTensor, optional
A scalar loss to be optimised.
"""
embedded_text = self.text_field_embedder(text)
mask = util.get_text_field_mask(text)
encoded_text = self.text_encoder(embedded_text, mask)
pooled = self.pool(encoded_text, mask)
ff_hidden = self.classifier_feedforward(pooled)
logits = self.prediction_layer(ff_hidden)
class_probs = F.softmax(logits, dim=1)
output_dict = {"logits": logits}
if label is not None:
loss = self.loss(logits, label)
output_dict["loss"] = loss
# compute F1 per label
for i in range(self.num_classes):
metric = self.label_f1_metrics[self.vocab.get_token_from_index(index=i, namespace="labels")]
metric(class_probs, label)
self.label_accuracy(logits, label)
return output_dict
#@overrides
def decode(self, output_dict: Dict[str, torch.Tensor]) -> Dict[str, torch.Tensor]:
class_probabilities = F.softmax(output_dict['logits'], dim=-1)
output_dict['class_probs'] = class_probabilities
return output_dict
def get_metrics(self, reset: bool = False) -> Dict[str, float]:
metric_dict = {}
sum_f1 = 0.0
for name, metric in self.label_f1_metrics.items():
metric_val = metric.get_metric(reset)
if self.verbose_metrics:
metric_dict[name + '_P'] = metric_val[0]
metric_dict[name + '_R'] = metric_val[1]
metric_dict[name + '_F1'] = metric_val[2]
sum_f1 += metric_val[2]
names = list(self.label_f1_metrics.keys())
total_len = len(names)
average_f1 = sum_f1 / total_len
metric_dict['average_F1'] = average_f1
metric_dict['accuracy'] = self.label_accuracy.get_metric(reset)
return metric_dict
The name is already taken. Something that’s already a part of AllenNLP uses that name already, so you need to pick a different one.
For the curious, AllenNLP creates a registry of models, so that you can select a model at the command line. (That’s what the decorator is doing.) This requires the names to be unique.
The name text_classifier was used by AllenNLP only after the external package you’re using used it. It worked in May 2019, when that file was last updated. But 17 months ago, AllenNLP started using it. So it’s not your fault; it’s a mismatch between those two packages (at least, in their current versions).