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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 guard_unassign(duplicate_analysis):
 """Return whether the transition 'unassign' can be performed or not """

    analysis = duplicate_analysis.getAnalysis()
    if wf.isTransitionAllowed(analysis, "unassign"):
        return True
    skip = ["retracted", "rejected", "unassigned"]
    if api.get_review_status(analysis) in skip:
        return True
    return analysis_guards.guard_unassign(duplicate_analysis)