Assigning a peer reviewer to a submission

Given a submission_id I can assign a peer reviewer to review a given student's submission using 

./assign-peer-reviewer.py Download assign-peer-reviewer.py

course_id assignment_id user_id submission_id

 

I can also assign a peer reviewer using:

./assign-assessor-as-peer-reviewer.py Download assign-assessor-as-peer-reviewer.py

course_id assignment_id assessor_id user_id

However, I am unable to assign an assessor to do a peer review until there is a submission_id for the potential submission. The submission_id seems to be created if I manually assign a peer reviewer, but otherwise there does not seem to be a submission_id.