[BB3] training command (#4747)
[BB3] training command (#4747)

* training command

* separating lines

Co-authored-by: Mojtaba Komeili <5d6b7c0a569ac7f92568c9267c04377ee5b86fc8@fb.com>
facebookresearch/ParlAI,facebookresearch/ParlAI,facebookresearch/ParlAI,facebookresearch/ParlAI,facebookresearch/ParlAI