public static ASMappingAddress asMappingAddress(String asn) {
        return new ASMappingAddress(asn);
    }
@Test
    public void testAsMappingAddressMethod() {
        String asn = "1";
        MappingAddress mappingAddress = MappingAddresses.asMappingAddress(asn);
        ASMappingAddress asMappingAddress =
                checkAndConvert(mappingAddress,
                                MappingAddress.Type.AS,
                                ASMappingAddress.class);
        assertThat(asMappingAddress.asNumber(), is(equalTo(asn)));
    }