main.py

from transformers import AutoModelForSequenceClassification, Trainer, TrainingArguments
from dataset import MyDataset
from data_collator import MyDataCollator

# Set hyperparameters
model_name = 'bert-base-uncased'
batch_size = 16
num_epochs = 3

# Load data
train_data = MyDataset('train.csv', AutoTokenizer.from_pretrained(model_name))
val_data = MyDataset('val.csv', AutoTokenizer.from_pretrained(model_name))

# Create data collator
data_collator = MyDataCollator(AutoTokenizer.from_pretrained(model_name))

# Create model
model = AutoModelForSequenceClassification.from_pretrained(model_name, num_labels=8)

# Create training arguments
training_args = TrainingArguments(
    output_dir='./results',
    num_train_epochs=num_epochs,
    per_device_train_batch_size=batch_size,
    per_device_eval_batch_size=batch_size,
    evaluation_strategy='epoch',
    save_total_limit=2,
    save_steps=500,
    load_best_model_at_end=True,
    metric_for_best_model='accuracy',
    greater_is_better=True,
    save_on_each_node=True,
)

# Create trainer
trainer = Trainer(
    model=model,
    args=training_args,
    train_dataset=train_data,
    eval_dataset=val_data,
    compute_metrics=lambda pred: {'accuracy': torch.sum(torch.argmax(pred.label_ids, dim=1) == torch.argmax(pred.predictions, dim=1))},
    data_collator=data_collator,
)

# Train model
trainer.train()