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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 normalize_locale_code(locale: Union[Locale, str]) -> str: """Determine the normalized locale code string. 'ko_KR' 'zh_Hant_TW' 'en_US' """

    if not isinstance(locale, Locale):
        locale = Locale.parse(locale.replace('-', '_'))
    return str(locale)