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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 init_nautilus(method):
 """Initialize nautilus method Parameters method Interactive method used for the process Returns ------- PreferenceInformation subclass to be initialized """


    print("Preference elicitation options:")
    print("\t1 - Percentages")
    print("\t2 - Relative ranks")
    print("\t3 - Direct")

    PREFCLASSES = [PercentageSpecifictation, RelativeRanking, DirectSpecification]

    pref_sel = int(
        _prompt_wrapper(
            "Reference elicitation ",
            default=u"%s" % (1),
            validator=NumberValidator([1, 3]),
        )
    )

    preference_class = PREFCLASSES[pref_sel - 1]

    print("Nadir: %s" % method.problem.nadir)
    print("Ideal: %s" % method.problem.ideal)

    if method.current_iter - method.user_iters:
        finished_iter = method.user_iters - method.current_iter
    else:
        finished_iter = 0
    new_iters = int(
        _prompt_wrapper(
            u"Ni: ", default=u"%s" % (method.current_iter), validator=NumberValidator()
        )
    )
    method.current_iter = new_iters
    method.user_iters = finished_iter + new_iters

    return preference_class