def deploy_service_registry_and_set_urls(
    private_keys, web3, contract_manager, service_registry_address
) -> Tuple[ServiceRegistry, List[str]]:
    urls = ["http://foo", "http://boo", "http://coo"]
    c1_client = JSONRPCClient(web3, private_keys[0])
    c1_service_proxy = ServiceRegistry(
        jsonrpc_client=c1_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )
    c2_client = JSONRPCClient(web3, private_keys[1])
    c2_service_proxy = ServiceRegistry(
        jsonrpc_client=c2_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )
    c3_client = JSONRPCClient(web3, private_keys[2])
    c3_service_proxy = ServiceRegistry(
        jsonrpc_client=c3_client,
        service_registry_address=service_registry_address,
        contract_manager=contract_manager,
    )

    # Test that getting a random service for an empty registry returns None
    pfs_address = get_random_service(c1_service_proxy, "latest")
    assert pfs_address is None

    # Test that setting the urls works
    c1_service_proxy.set_url(urls[0])
    c2_service_proxy.set_url(urls[1])
    c3_service_proxy.set_url(urls[2])

    return c1_service_proxy, urls
def test_packed(self):
        class X(Structure):
            _fields_ = [("a", c_byte),
                        ("b", c_longlong)]
            _pack_ = 1

        self.assertEqual(sizeof(X), 9)
        self.assertEqual(X.b.offset, 1)

        class X(Structure):
            _fields_ = [("a", c_byte),
                        ("b", c_longlong)]
            _pack_ = 2
        self.assertEqual(sizeof(X), 10)
        self.assertEqual(X.b.offset, 2)

        class X(Structure):
            _fields_ = [("a", c_byte),
                        ("b", c_longlong)]
            _pack_ = 4
        self.assertEqual(sizeof(X), 12)
        self.assertEqual(X.b.offset, 4)

        import struct
        longlong_size = struct.calcsize("q")
        longlong_align = struct.calcsize("bq") - longlong_size

        class X(Structure):
            _fields_ = [("a", c_byte),
                        ("b", c_longlong)]
            _pack_ = 8

        self.assertEqual(sizeof(X), longlong_align + longlong_size)
        self.assertEqual(X.b.offset, min(8, longlong_align))


        d = {"_fields_": [("a", "b"),
                          ("b", "q")],
             "_pack_": -1}
        self.assertRaises(ValueError, type(Structure), "X", (Structure,), d)

        # Issue 15989
        d = {"_fields_": [("a", c_byte)],
             "_pack_": _testcapi.INT_MAX + 1}
        self.assertRaises(ValueError, type(Structure), "X", (Structure,), d)
        d = {"_fields_": [("a", c_byte)],
             "_pack_": _testcapi.UINT_MAX + 2}
        self.assertRaises(ValueError, type(Structure), "X", (Structure,), d)