new_branch.py

# create a new branch
new_branch = repo.create_head('processing_test') 
 
# create upstream remote urls
upstream = repo.create_remote('upstream', repo_qgis)
 
origin = repo.remotes.origin
upstream = repo.remotes.upstream
 
# get heads and checkout new branch
heads = repo.heads
heads.new_branch.checkout()
 
# pull to new branch from qgis
upstream.pull(refspec=heads.master)