def train_mapper(sample):
    #print(sample)
    img_path,label=sample
    try:
        img=Image.open(img_path)
        #进行了简单的图像变换，这里对图像进行crop修剪操作，输出img的维度为(3, 100, 100)
        img = paddle.dataset.image.simple_transform(im=img,          #输入图片是HWC   
                                                resize_size=100, # 剪裁图片
                                                crop_size=100, 
                                                is_color=True,  #彩色图像
                                                is_train=True)
        #将img数组进行进行归一化处理，得到0到1之间的数值
        img= img.flatten().astype('float32')/255.0
        return img,int(label)
    except:
        pass
def train_r(train_list,buffered_size=1024):
    def reader():
        with open(train_list,'r') as f:
            lines=f.readlines()
            for line in lines:
                img_path,label=line.split('\t')
                yield img_path,label
    return paddle.reader.xmap_readers(train_mapper,reader,cpu_count(),buffered_size)
 
trainer_reader = train_r(train_list="data/data10954/train.txt")
temp_reader = paddle.batch(trainer_reader,
                            batch_size=4)
temp_data=next(temp_reader())
print(temp_data)

yield img_path,label 之前 print(img_path,label)结果是

但是在传入train_mapper后打印sample结果是：

会出现这种有时未换行的情况。为什么会出现这种结果，是我哪里写的有问题吗？