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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 translate_month_abbr( date_str, source_lang=DEFAULT_DATE_LANG, target_lang=DEFAULT_DATE_LANG):
 """Translate the month abbreviation from one locale to another."""

    month_num, month_abbr = get_month_from_date_str(date_str, source_lang)
    with calendar.different_locale(LOCALES[target_lang]):
        translated_abbr = calendar.month_abbr[month_num]
        return re.sub(
            month_abbr, translated_abbr, date_str, flags=re.IGNORECASE)