def METHOD_NAME():
    cookies = ["UUID=12345", "SSID=0xdeadbeef"]
    warning_message = "Can't encode more than one cookie in the response. Sending the last cookie only."
    serializer = SingleValueHeadersSerializer()
    with pytest.warns(match=warning_message):
        payload = serializer.serialize(cookies=cookies, headers={})
    assert payload["headers"]["Set-Cookie"] == cookies[-1]