__init__.py 文件源码

def snowball_stem(word, lang='english'):
    global _nltk_snowball_stemmer
    try:
        _nltk_snowball_stemmer
    except NameError:
        available_languages = ['danish', 'dutch', 'english', 'finnish', 'french',
                               'german', 'german2', 'hungarian', 'italian',
                               'kraaij_pohlmann', 'lovins', 'norwegian',
                               'porter', 'portuguese', 'romanian', 'russian',
                               'spanish', 'swedish', 'turkish']
        assert lang in available_languages, "Snowball Stemmer for {} not available".format(lang)
        # Checks that the snowball data was previously downloaded.
        download('snowball_data', quiet=True)
        _nltk_snowball_stemmer = SnowballStemmer(lang)
    return _nltk_snowball_stemmer.stem(word)