在PyTorch Lightning中实现预处理的位置(例如，对输入文本进行标记)

import torch
from torch.utils.data import Dataset, DataLoader
from torchtext.data.utils import get_tokenizer
from torchtext.vocab import build_vocab_from_iterator

class MyDataset(Dataset):
    def __init__(self, data):
        self.data = data

    def __getitem__(self, index):
        return self.data[index]

    def __len__(self):
        return len(self.data)

class MyDataModule(pl.LightningDataModule):
    def __init__(self, train_data, val_data, test_data):
        super().__init__()
        self.train_data = train_data
        self.val_data = val_data
        self.test_data = test_data
        self.tokenizer = get_tokenizer('basic_english')

    def prepare_data(self):
        # 下载数据集或准备数据文件的操作
        pass

    def setup(self, stage=None):
        # 数据预处理的操作
        train_tokens = [self.tokenizer(item) for item in self.train_data]
        val_tokens = [self.tokenizer(item) for item in self.val_data]
        test_tokens = [self.tokenizer(item) for item in self.test_data]

        self.vocab = build_vocab_from_iterator(train_tokens)
        self.train_dataset = MyDataset(train_tokens)
        self.val_dataset = MyDataset(val_tokens)
        self.test_dataset = MyDataset(test_tokens)

    def train_dataloader(self):
        return DataLoader(self.train_dataset, batch_size=32)

    def val_dataloader(self):
        return DataLoader(self.val_dataset, batch_size=32)

    def test_dataloader(self):
        return DataLoader(self.test_dataset, batch_size=32)

# 使用数据模块
train_data = ['This is a sample sentence.', 'Another sentence.']
val_data = ['Yet another sentence.', 'One more sentence.']
test_data = ['Some test sentence.', 'Another test sentence.']

data_module = MyDataModule(train_data, val_data, test_data)
data_module.prepare_data()
data_module.setup()

train_loader = data_module.train_dataloader()
val_loader = data_module.val_dataloader()
test_loader = data_module.test_dataloader()

for batch in train_loader:
    # 在训练过程中使用预处理后的数据进行模型训练
    inputs = batch
    outputs = model(inputs)
    # ...