pytorch报错：PicklingError: Can’t pickle ＜function at 0x000001EA6923EAF0＞: attribute lookup on main fai

报错显示

任务背景

使用pytorch中的 DataLoader 生成数据集（cifar2数据集）的时候，想查看图像数据的维度，这时候打印出错

程序：

## num_workers (int, optional): how many subprocesses to use for data loading.
dl_train = DataLoader(ds_train, batch_size = 50, shuffle = True, num_workers=3)
dl_valid = DataLoader(ds_valid, batch_size = 50, shuffle = True, num_workers=3)# Pytorch的图片默认顺序是 Batch,Channel,Width,Height
for x,y in dl_train:print(x.shape,y.shape) break

解决方案

https://icode9.com/content-4-1117833.html

将 参数 num_workers = 3 修改为 num_workers = 0

然后问题得到解决。