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227 lines
7 KiB
Python
227 lines
7 KiB
Python
import os
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from toxicity_ml_pipeline.settings.default_settings_tox import LOCAL_DIR, MAX_SEQ_LENGTH
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try:
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from toxicity_ml_pipeline.optim.losses import MaskedBCE
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except ImportError:
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print('No MaskedBCE loss')
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from toxicity_ml_pipeline.utils.helpers import execute_command
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import tensorflow as tf
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try:
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from twitter.cuad.representation.models.text_encoder import TextEncoder
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except ModuleNotFoundError:
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print("No TextEncoder package")
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try:
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from transformers import TFAutoModelForSequenceClassification
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except ModuleNotFoundError:
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print("No HuggingFace package")
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LOCAL_MODEL_DIR = os.path.join(LOCAL_DIR, "models")
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def reload_model_weights(weights_dir, language, **kwargs):
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optimizer = tf.keras.optimizers.Adam(0.01)
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model_type = (
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"twitter_bert_base_en_uncased_mlm"
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if language == "en"
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else "twitter_multilingual_bert_base_cased_mlm"
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)
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model = load(optimizer=optimizer, seed=42, model_type=model_type, **kwargs)
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model.load_weights(weights_dir)
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return model
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def _locally_copy_models(model_type):
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if model_type == "twitter_multilingual_bert_base_cased_mlm":
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preprocessor = "bert_multi_cased_preprocess_3"
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elif model_type == "twitter_bert_base_en_uncased_mlm":
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preprocessor = "bert_en_uncased_preprocess_3"
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else:
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raise NotImplementedError
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copy_cmd = """mkdir {local_dir}
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gsutil cp -r ...
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gsutil cp -r ..."""
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execute_command(
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copy_cmd.format(model_type=model_type, preprocessor=preprocessor, local_dir=LOCAL_MODEL_DIR)
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)
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return preprocessor
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def load_encoder(model_type, trainable):
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try:
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model = TextEncoder(
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max_seq_lengths=MAX_SEQ_LENGTH,
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model_type=model_type,
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cluster="gcp",
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trainable=trainable,
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enable_dynamic_shapes=True,
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)
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except (OSError, tf.errors.AbortedError) as e:
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print(e)
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preprocessor = _locally_copy_models(model_type)
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model = TextEncoder(
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max_seq_lengths=MAX_SEQ_LENGTH,
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local_model_path=f"models/{model_type}",
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local_preprocessor_path=f"models/{preprocessor}",
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cluster="gcp",
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trainable=trainable,
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enable_dynamic_shapes=True,
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)
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return model
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def get_loss(loss_name, from_logits, **kwargs):
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loss_name = loss_name.lower()
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if loss_name == "bce":
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print("Binary CE loss")
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return tf.keras.losses.BinaryCrossentropy(from_logits=from_logits)
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if loss_name == "cce":
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print("Categorical cross-entropy loss")
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return tf.keras.losses.CategoricalCrossentropy(from_logits=from_logits)
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if loss_name == "scce":
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print("Sparse categorical cross-entropy loss")
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return tf.keras.losses.SparseCategoricalCrossentropy(from_logits=from_logits)
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if loss_name == "focal_bce":
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gamma = kwargs.get("gamma", 2)
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print("Focal binary CE loss", gamma)
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return tf.keras.losses.BinaryFocalCrossentropy(gamma=gamma, from_logits=from_logits)
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if loss_name == 'masked_bce':
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multitask = kwargs.get("multitask", False)
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if from_logits or multitask:
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raise NotImplementedError
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print(f'Masked Binary Cross Entropy')
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return MaskedBCE()
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if loss_name == "inv_kl_loss":
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raise NotImplementedError
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raise ValueError(
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f"This loss name is not valid: {loss_name}. Accepted loss names: BCE, masked BCE, CCE, sCCE, "
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f"Focal_BCE, inv_KL_loss"
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)
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def _add_additional_embedding_layer(doc_embedding, glorot, seed):
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doc_embedding = tf.keras.layers.Dense(768, activation="tanh", kernel_initializer=glorot)(doc_embedding)
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doc_embedding = tf.keras.layers.Dropout(rate=0.1, seed=seed)(doc_embedding)
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return doc_embedding
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def _get_bias(**kwargs):
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smart_bias_value = kwargs.get('smart_bias_value', 0)
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print('Smart bias init to ', smart_bias_value)
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output_bias = tf.keras.initializers.Constant(smart_bias_value)
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return output_bias
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def load_inhouse_bert(model_type, trainable, seed, **kwargs):
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inputs = tf.keras.layers.Input(shape=(), dtype=tf.string)
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encoder = load_encoder(model_type=model_type, trainable=trainable)
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doc_embedding = encoder([inputs])["pooled_output"]
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doc_embedding = tf.keras.layers.Dropout(rate=0.1, seed=seed)(doc_embedding)
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glorot = tf.keras.initializers.glorot_uniform(seed=seed)
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if kwargs.get("additional_layer", False):
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doc_embedding = _add_additional_embedding_layer(doc_embedding, glorot, seed)
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if kwargs.get('content_num_classes', None):
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probs = get_last_layer(glorot=glorot, last_layer_name='target_output', **kwargs)(doc_embedding)
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second_probs = get_last_layer(num_classes=kwargs['content_num_classes'],
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last_layer_name='content_output',
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glorot=glorot)(doc_embedding)
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probs = [probs, second_probs]
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else:
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probs = get_last_layer(glorot=glorot, **kwargs)(doc_embedding)
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model = tf.keras.models.Model(inputs=inputs, outputs=probs)
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return model, False
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def get_last_layer(**kwargs):
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output_bias = _get_bias(**kwargs)
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if 'glorot' in kwargs:
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glorot = kwargs['glorot']
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else:
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glorot = tf.keras.initializers.glorot_uniform(seed=kwargs['seed'])
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layer_name = kwargs.get('last_layer_name', 'dense_1')
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if kwargs.get('num_classes', 1) > 1:
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last_layer = tf.keras.layers.Dense(
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kwargs["num_classes"], activation="softmax", kernel_initializer=glorot,
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bias_initializer=output_bias, name=layer_name
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)
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elif kwargs.get('num_raters', 1) > 1:
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if kwargs.get('multitask', False):
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raise NotImplementedError
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last_layer = tf.keras.layers.Dense(
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kwargs['num_raters'], activation="sigmoid", kernel_initializer=glorot,
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bias_initializer=output_bias, name='probs')
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else:
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last_layer = tf.keras.layers.Dense(
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1, activation="sigmoid", kernel_initializer=glorot,
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bias_initializer=output_bias, name=layer_name
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)
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return last_layer
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def load_bertweet(**kwargs):
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bert = TFAutoModelForSequenceClassification.from_pretrained(
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os.path.join(LOCAL_MODEL_DIR, "bertweet-base"),
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num_labels=1,
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classifier_dropout=0.1,
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hidden_size=768,
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)
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if "num_classes" in kwargs and kwargs["num_classes"] > 2:
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raise NotImplementedError
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return bert, True
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def load(
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optimizer,
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seed,
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model_type="twitter_multilingual_bert_base_cased_mlm",
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loss_name="BCE",
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trainable=True,
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**kwargs,
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):
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if model_type == "bertweet-base":
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model, from_logits = load_bertweet()
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else:
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model, from_logits = load_inhouse_bert(model_type, trainable, seed, **kwargs)
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pr_auc = tf.keras.metrics.AUC(curve="PR", name="pr_auc", from_logits=from_logits)
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roc_auc = tf.keras.metrics.AUC(curve="ROC", name="roc_auc", from_logits=from_logits)
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loss = get_loss(loss_name, from_logits, **kwargs)
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if kwargs.get('content_num_classes', None):
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second_loss = get_loss(loss_name=kwargs['content_loss_name'], from_logits=from_logits)
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loss_weights = {'content_output': kwargs['content_loss_weight'], 'target_output': 1}
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model.compile(
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optimizer=optimizer,
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loss={'content_output': second_loss, 'target_output': loss},
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loss_weights=loss_weights,
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metrics=[pr_auc, roc_auc],
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)
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else:
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model.compile(
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optimizer=optimizer,
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loss=loss,
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metrics=[pr_auc, roc_auc],
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)
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print(model.summary(), "logits: ", from_logits)
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return model |