如何获取我在Pytorch中放入Dataloader的图像的文件名

import os
from PIL import Image
from torch.utils.data import Dataset, DataLoader

class CustomDataset(Dataset):
    def __init__(self, root_dir):
        self.root_dir = root_dir
        self.file_list = os.listdir(root_dir)

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

    def __getitem__(self, idx):
        img_name = self.file_list[idx]
        img_path = os.path.join(self.root_dir, img_name)
        image = Image.open(img_path)
        # 其他数据预处理操作...

        return image, img_name

# 假设图像文件存放在'./images'目录下
dataset = CustomDataset('./images')
dataloader = DataLoader(dataset, batch_size=32, shuffle=True)

for images, filenames in dataloader:
    # images为图像数据，filenames为对应的文件名
    for filename in filenames:
        print(filename)