The self.transfer in PreExtraction class

[zhangzy5]

There is a self.transfer module in PreExtraction class. Since I don't see it in figures, may I ask for the function of it. And if it can be removed.

[kliocon]

No, at first I was also confused, but later I realized that this was actually part of the bottleneck structure design and could understand. Without this module, it would be impossible to map to a deeper dimension