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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 get_i18n_day_name(day_nb, display='short', ln=None):
 """Get the string representation of a weekday, internationalized @param day_nb: number of weekday UNIX like. => 0=Sunday @param ln: language for output @return: the string representation of the day """

    ln = default_ln(ln)
    _ = gettext_set_language(ln)
    if display == 'short':
        days = {0: _("Sun"),
                1: _("Mon"),
                2: _("Tue"),
                3: _("Wed"),
                4: _("Thu"),
                5: _("Fri"),
                6: _("Sat")}
    else:
        days = {0: _("Sunday"),
                1: _("Monday"),
                2: _("Tuesday"),
                3: _("Wednesday"),
                4: _("Thursday"),
                5: _("Friday"),
                6: _("Saturday")}

    return days[day_nb]