API has changed, `state_steps` argument must contain a list of singleton tensors

[TranHungAnh96]

I got this issue when I run the a3c.py, I also found someone has the same error as me on this link facebookresearch/fairscale#1083
I thought this because of the pytorch version, could you give me the pytorch version you used for this code?
Btw, does anyone meet the same thing, how can you guys fix this? Thanks a lot.