Pytorch torchvision. Datasets. ImageFolder Found 0 files in subfolders error

recently in learning pytorch actual combat computer vision book, the case of cat and dog battle, according to the original code [external chain picture transfer failure, the source station may have anti-hotlinking mechanism, suggested to save the picture directly upload (C:\Users\dell\AppData\ Typora\typora-user-images\1602066856682.png)

encountered an error loading ImageFolder

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create a new subfolder in the valid, error resolution.