Sorry, still did not understand data loader.
Is this part the Custom Data Loader in the tutorial?
“”“Face Landmarks dataset.”""
def __init__(self, csv_file, root_dir, transform=None):
    """
    Args:
        csv_file (string): Path to the csv file with annotations.
        root_dir (string): Directory with all the images.
        transform (callable, optional): Optional transform to be applied
            on a sample.
    """
    self.landmarks_frame = pd.read_csv(csv_file)
    self.root_dir = root_dir
    self.transform = transform

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

def __getitem__(self, idx):
    if torch.is_tensor(idx):
        idx = idx.tolist()

    img_name = os.path.join(self.root_dir,
                            self.landmarks_frame.iloc[idx, 0])
    image = io.imread(img_name)
    landmarks = self.landmarks_frame.iloc[idx, 1:]
    landmarks = np.array([landmarks])
    landmarks = landmarks.astype('float').reshape(-1, 2)
    sample = {'image': image, 'landmarks': landmarks}

    if self.transform:
        sample = self.transform(sample)

    return sample