How to use the pypinyin.pinyin function in pypinyin

def test_pinyin_finals():
    """只包含韵母的词语"""
    hans = '嗷嗷'
    assert pinyin(hans) == [['\xe1o'], ['\xe1o']]
    assert pinyin(hans + 'abc') == [['\xe1o'], ['\xe1o'], ['abc']]
    assert pinyin(hans, NORMAL) == [['ao'], ['ao']]
    assert pinyin(hans, TONE) == [['\xe1o'], ['\xe1o']]
    assert pinyin(hans, TONE2) == [['a2o'], ['a2o']]
    assert pinyin(hans, TONE3) == [['ao2'], ['ao2']]
    assert pinyin(hans, INITIALS) == [[''], ['']]
    assert pinyin(hans, FIRST_LETTER) == [['a'], ['a']]
    assert pinyin(hans, BOPOMOFO) == [['ㄠˊ'], ['ㄠˊ']]
    assert pinyin(hans, BOPOMOFO_FIRST) == [['ㄠ'], ['ㄠ']]
    assert pinyin(hans, CYRILLIC) == [['ао2'], ['ао2']]
    assert pinyin(hans, CYRILLIC_FIRST) == [['а'], ['а']]
    assert pinyin(hans, heteronym=True) == [['\xe1o'], ['\xe1o']]
    assert pinyin('啊', heteronym=True) == \
        [['a', 'è', 'ā', 'á', 'ǎ', 'à']]
    assert pinyin(hans, style=FINALS) == [['ao'], ['ao']]
    assert pinyin(hans, style=FINALS_TONE) == [['\xe1o'], ['\xe1o']]
    assert pinyin(hans, style=FINALS_TONE2) == [['a2o'], ['a2o']]
    assert pinyin(hans, style=FINALS_TONE3) == [['ao2'], ['ao2']]

def test_uei(hans, kwargs, result):
    assert lazy_pinyin(hans, **kwargs) == result
    assert pinyin(hans, **kwargs) == [result]

hans = '中心'
    # 默认风格，带声调
    assert pinyin(hans) == [['zh\u014dng'], ['x\u012bn']]
    assert pinyin(hans, strict=False) == [['zh\u014dng'], ['x\u012bn']]
    # 普通风格，不带声调
    assert pinyin(hans, NORMAL) == [['zhong'], ['xin']]
    assert pinyin(hans, NORMAL, strict=False) == [['zhong'], ['xin']]
    # 声调风格，拼音声调在韵母第一个字母上
    assert pinyin(hans, TONE) == [['zh\u014dng'], ['x\u012bn']]
    assert pinyin(hans, TONE, strict=False) == [['zh\u014dng'], ['x\u012bn']]
    # 声调风格2，即拼音声调在各个声母之后，用数字 [1-4] 进行表示
    assert pinyin(hans, TONE2) == [['zho1ng'], ['xi1n']]
    assert pinyin(hans, TONE2, strict=False) == [['zho1ng'], ['xi1n']]
    # 声调风格3，即拼音声调在各个拼音之后，用数字 [1-4] 进行表示
    assert pinyin(hans, TONE3) == [['zhong1'], ['xin1']]
    assert pinyin(hans, TONE3, strict=False) == [['zhong1'], ['xin1']]
    # 声母风格，只返回各个拼音的声母部分
    assert pinyin(hans, INITIALS) == [['zh'], ['x']]
    assert pinyin(hans, INITIALS, strict=False) == [['zh'], ['x']]
    # 首字母风格，只返回拼音的首字母部分
    assert pinyin(hans, FIRST_LETTER) == [['z'], ['x']]
    assert pinyin(hans, FIRST_LETTER, strict=False) == [['z'], ['x']]
    # 注音风格，带声调
    assert pinyin(hans, BOPOMOFO) == [['ㄓㄨㄥ'], ['ㄒㄧㄣ']]
    assert pinyin(hans, BOPOMOFO, strict=False) == [['ㄓㄨㄥ'], ['ㄒㄧㄣ']]
    # 注音风格，首字母
    assert pinyin(hans, BOPOMOFO_FIRST) == [['ㄓ'], ['ㄒ']]
    assert pinyin(hans, BOPOMOFO_FIRST, strict=False) == [['ㄓ'], ['ㄒ']]
    # test CYRILLIC style
    assert pinyin(hans, CYRILLIC) == [['чжун1'], ['синь1']]
    assert pinyin(hans, CYRILLIC, strict=False) == [['чжун1'], ['синь1']]
    # CYRILLIC_FIRST style return only first letters

assert pinyin(hans, TONE2, strict=False) == [['zho1ng'], ['xi1n']]
    # 声调风格3，即拼音声调在各个拼音之后，用数字 [1-4] 进行表示
    assert pinyin(hans, TONE3) == [['zhong1'], ['xin1']]
    assert pinyin(hans, TONE3, strict=False) == [['zhong1'], ['xin1']]
    # 声母风格，只返回各个拼音的声母部分
    assert pinyin(hans, INITIALS) == [['zh'], ['x']]
    assert pinyin(hans, INITIALS, strict=False) == [['zh'], ['x']]
    # 首字母风格，只返回拼音的首字母部分
    assert pinyin(hans, FIRST_LETTER) == [['z'], ['x']]
    assert pinyin(hans, FIRST_LETTER, strict=False) == [['z'], ['x']]
    # 注音风格，带声调
    assert pinyin(hans, BOPOMOFO) == [['ㄓㄨㄥ'], ['ㄒㄧㄣ']]
    assert pinyin(hans, BOPOMOFO, strict=False) == [['ㄓㄨㄥ'], ['ㄒㄧㄣ']]
    # 注音风格，首字母
    assert pinyin(hans, BOPOMOFO_FIRST) == [['ㄓ'], ['ㄒ']]
    assert pinyin(hans, BOPOMOFO_FIRST, strict=False) == [['ㄓ'], ['ㄒ']]
    # test CYRILLIC style
    assert pinyin(hans, CYRILLIC) == [['чжун1'], ['синь1']]
    assert pinyin(hans, CYRILLIC, strict=False) == [['чжун1'], ['синь1']]
    # CYRILLIC_FIRST style return only first letters
    assert pinyin(hans, CYRILLIC_FIRST) == [['ч'], ['с']]
    assert pinyin(hans, CYRILLIC_FIRST, strict=False) == [['ч'], ['с']]
    # 启用多音字模式
    assert pinyin(hans, heteronym=True) == [['zh\u014dng', 'zh\xf2ng'],
                                            ['x\u012bn']]
    assert pinyin(hans, heteronym=True, strict=False) == \
        [['zh\u014dng', 'zh\xf2ng'], ['x\u012bn']]
    # 韵母风格1，只返回各个拼音的韵母部分，不带声调
    assert pinyin(hans, style=FINALS) == [['ong'], ['in']]
    assert pinyin(hans, style=FINALS, strict=False) == [['ong'], ['in']]
    # 韵母风格2，带声调，声调在韵母第一个字母上
    assert pinyin(hans, style=FINALS_TONE) == [['\u014dng'], ['\u012bn']]

def get_acronym(str_data):
        """
        获取字符串的首字母
        :param str_data: 字符串
        :return: 字符串
        """
        return "".join([i[0][0] for i in pinyin(str_data)])