def _nltk_to_iso369_3(name):
    """
    Map a country name to an ISO 369-3 code.

    See https://en.wikipedia.org/wiki/List_of_ISO_639-1_codes for an overview.
    """
    name = name.lower()
    return {'danish': 'dan',
            'dutch': 'nld',
            'english': 'eng',
            'french': 'fra',
            'finnish': 'fin',
            'german': 'deu',
            'hungarian': 'hun',
            'italian': 'ita',
            'norwegian': 'nor',
            'portuguese': 'por',
            'russian': 'rus',
            'spanish': 'spa',
            'swedish': 'swe',
            'turkish': 'tur'}.get(name, None)