@pytest.mark.parametrize('string, ans', [(b'Hello', b'hello'), (b'here', b'here'), (b'LOVELY', b'lovely')])
def test_to_lower(string, ans):
    c_lib.toLowerCase(string)
    assert (string == ans)
@pytest.mark.parametrize('string, ans', [(b'Hello', b'hello'), (b'here', b'here'), (b'LOVELY', b'lovely')])
def test_to_lower(string, ans):
    c_lib.toLowerCase(string)
    assert (string == ans)