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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_retract(analysis):
 """ Return whether the transition "retract" can be performed or not """

    # Cannot retract if there are dependents that cannot be retracted
    if not is_transition_allowed(analysis.getDependents(), "retract"):
        return False

    dependencies = analysis.getDependencies()
    if not dependencies:
        return True

    # Cannot retract if all dependencies have been verified
    if all(map(lambda an: IVerified.providedBy(an), dependencies)):
        return False

    return True