what is bs_scale for?

[indigopyj]

IF/deepfloyd_if/modules/base.py

Line 99 in ffc8163

bs_scale = 2 if positive_t5_embs is None else 3

I am interested in inpainting model and I found the variable 'bs_scale'.
However, I don't know what is the purpose of this variable.
Why do we have to multiple batch_size by 2 ?

Does anyone know about it?