def test_filter_languages():
    filtered_langs = dictcli.filter_languages(langs(), ['af-ZA'])
    assert filtered_langs == [afrikaans()]

    filtered_langs = dictcli.filter_languages(langs(), ['pl-PL', 'en-US'])
    assert filtered_langs == [english(), polish()]

    with pytest.raises(dictcli.InvalidLanguageError):
        dictcli.filter_languages(langs(), ['pl-PL', 'en-GB'])
def test_filter_languages():
    filtered_langs = dictcli.filter_languages(langs(), ['af-ZA'])
    assert filtered_langs == [afrikaans()]

    filtered_langs = dictcli.filter_languages(langs(), ['pl-PL', 'en-US'])
    assert filtered_langs == [english(), polish()]

    with pytest.raises(dictcli.InvalidLanguageError):
        dictcli.filter_languages(langs(), ['pl-PL', 'en-GB'])