def test_is_lucky_8(self): eq_(True, is_lucky(8))
def test_is_lucky_number_91(self): eq_(False, is_lucky(91))
def test_is_lucky_number_18(self): eq_(True, is_lucky(18))
def test_is_lucky_number_81(self): eq_(True, is_lucky(81))
def test_is_lucky_number_less_than_8(self): eq_(False, is_lucky(5))