How to use the pykakasi.scripts.K2 function in pykakasi

def test_K2a():
    TESTS = [
        (u"カンタン", ("ka", 1)),
        (u"ニャ", ("nya", 2)),
        (u"ッキ", ("kki", 2)),
        (u"ッファ", ("ffa", 3)),
        (u"シツモン", ("shi", 1)),
        (u"チガイ", ("chi", 1)),
        (u"ジ", ("ji", 1)),
    ]
    h = pykakasi.scripts.K2("a")
    for case, result in TESTS:
        assert h.convert(case) == result

def test_K2H():
    TESTS = [
        (u"カンタン", (u"かんたん", 4)),
        (u"ニャ", (u"にゃ", 2)),
        (u"ッキ", (u"っき", 2)),
        (u"ッファ", (u"っふぁ", 3)),
        (u"シツモン", (u"しつもん", 4)),
        (u"チガイ", (u"ちがい", 3)),
    ]
    h = pykakasi.scripts.K2("H")
    for case, result in TESTS:
        assert h.convert(case) == result

(u"ファジー", ("fa", 2)),
        (u"ジー", ("zi", 1)),
        (u"ウォークマン", ("u", 1)),
        (u"キャ", ("kya", 2)), (u"キュ", ("kyu", 2)), (u"キョ", ("kyo", 2)),
        (u"シャ", ("sya", 2)), (u"シュ", ("syu", 2)), (u"ショ", ("syo", 2)),
        (u"チャ", ("tya", 2)), (u"チュ", ("tyu", 2)), (u"チョ", ("tyo", 2)),
        (u"ニャ", ("nya", 2)), (u"ニュ", ("nyu", 2)), (u"ニョ", ("nyo", 2)),
        (u"リャ", ("rya", 2)), (u"リュ", ("ryu", 2)), (u"リョ", ("ryo", 2)),
        (u"ザ", ("za", 1)), (u"ジ", ("zi", 1)), (u"ズ", ("zu", 1)),
        (u"ゼ", ("ze", 1)), (u"ゾ", ("zo", 1)),
        (u"ダ", ("da", 1)), (u"ヂ", ("zi", 1)), (u"ヅ", ("zu", 1)),
        (u"デ", ("de", 1)), (u"ド", ("do", 1)),
        (u"タ", ("ta", 1)), (u"チ", ("ti", 1)), (u"ツ", ("tu", 1)),
        (u"テ", ("te", 1)), (u"ト", ("to", 1))
    ]
    h = pykakasi.scripts.K2("a", method="Kunrei")
    for case, result in TESTS:
        assert h.convert(case) == result