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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def publish(branch, full_force=False):
 """Publish that branch, i.e. push it to origin"""

    checkout(branch)
    try:
        push('--force --set-upstream origin', branch)
    except ExistingReference:
        if full_force:
            push('origin --delete', branch)
            push('--force --set-upstream origin', branch)