How to use the blackhole.child.Child function in blackhole

def test_start():
    socks = [{"sock": None, "ssl": None}, {"sock": None, "ssl": "abc"}]
    child = Child("", "", socks, "1")
    with mock.patch("asyncio.Task"), mock.patch(
        "blackhole.child.Child.heartbeat"
    ), mock.patch("{0}.run_forever".format(_LOOP)), mock.patch(
        "blackhole.child.Child.stop"
    ), mock.patch(
        "os._exit"
    ) as mock_exit:
        child.start()
    assert mock_exit.called is True

async def test_child_heartbeat_started(event_loop):
    up_read, up_write = os.pipe()
    down_read, down_write = os.pipe()
    os.close(up_write)
    os.close(down_read)
    child = Child(up_read, down_write, [], "1")
    child.loop = event_loop
    child._started = True
    sp = StreamProtocol()
    sp.reader = asyncio.StreamReader()

    async def _reset():
        sp.reader.feed_data(protocols.PING)
        child._started = False

    reset_task = asyncio.Task(_reset())
    with mock.patch(
        "blackhole.streams.StreamProtocol", return_value=sp
    ), mock.patch("asyncio.Task") as mock_task, mock.patch(
        "blackhole.child.Child._start"
    ) as mock_start, mock.patch(
        "blackhole.child.Child.stop"

def test_initiation():
    Child("", "", [], "1")

def test_stop():
    socks = [{"sock": None, "ssl": None}, {"sock": None, "ssl": "abc"}]
    child = Child("", "", socks, "1")
    child.loop = mock.MagicMock()
    child.clients.append(mock.MagicMock())
    child.servers.append(mock.MagicMock())
    child.heartbeat_task = mock.MagicMock()
    child.server_task = mock.MagicMock()

    with mock.patch("os._exit") as mock_exit, mock.patch(
        "{0}.run_until_complete".format(_LOOP)
    ):
        child.stop()
    assert mock_exit.called is True

def test_stop_runtime_exception():
    socks = [{"sock": None, "ssl": None}, {"sock": None, "ssl": "abc"}]
    child = Child("", "", socks, "1")
    child.loop = mock.MagicMock()
    child.clients.append(mock.MagicMock())
    child.servers.append(mock.MagicMock())
    child.heartbeat_task = mock.MagicMock()
    child.server_task = mock.MagicMock()

    with mock.patch("os._exit") as mock_exit, mock.patch(
        "{0}.stop".format(_LOOP), side_effect=RuntimeError
    ):
        child.stop()
    assert mock_exit.called is True

async def test_start_child_loop(event_loop):
    sock = _socket("127.0.0.1", 0, socket.AF_INET)
    socks = ({"sock": sock, "ssl": None},)
    child = Child("", "", socks, "1")
    child.loop = event_loop
    await child._start()
    assert len(child.servers) == 1
    for server in child.servers:
        server.close()

def setup_child(self):
        """Basic setup for the child process and starting it."""
        setgid()
        setuid()
        asyncio.set_event_loop(None)
        if setproctitle:
            setproctitle.setproctitle("blackhole: worker")
        process = Child(self.up_read, self.down_write, self.socks, self.idx)
        process.start()