Results 2 issues of Ready

Hi, I find that the 'self.mask_token' has not been defined. So I can't run the pre-train code. Can you tell me how to solve it? Thanks!

root ├── images_train │ ├── 0000 # First four letters of the image name │ │ ├── 0000000 # Image Binary │ │ ├── 0000001 │ │ └── ... │...