public boolean has(long bitmask) {
        return (bits & bitmask) == bitmask;
    }
@Test
    public void has() {
        Services services = Services.of(Services.NODE_BLOOM | Services.NODE_WITNESS);
        assertTrue(services.has(Services.NODE_BLOOM));
        assertTrue(services.has(Services.NODE_WITNESS));
        assertTrue(services.has(Services.NODE_BLOOM | Services.NODE_WITNESS));
        assertFalse(services.has(Services.NODE_BITCOIN_CASH));
        assertFalse(services.has(Services.NODE_BLOOM | Services.NODE_WITNESS | Services.NODE_BITCOIN_CASH));
    }