static void removeOurDevice(OmemoDevice userDevice, Collection<OmemoDevice> devices) {
        if (devices.contains(userDevice)) {
            devices.remove(userDevice);
        }
    }
@Test
    public void removeOurDeviceTest() throws XmppStringprepException {
        OmemoDevice a = new OmemoDevice(JidCreate.bareFrom("a@b.c"), 123);
        OmemoDevice b = new OmemoDevice(JidCreate.bareFrom("a@b.c"), 124);

        HashSet<OmemoDevice> devices = new HashSet<>();
        devices.add(a); devices.add(b);

        assertTrue(devices.contains(a));
        assertTrue(devices.contains(b));
        OmemoService.removeOurDevice(a, devices);

        assertFalse(devices.contains(a));
        assertTrue(devices.contains(b));
    }