async def METHOD_NAME(client):
    """Test connection works."""
    try:
        rr = await client.read_coils(32, 1, slave=1)
        assert len(rr.bits) == 8
        rr = await client.read_holding_registers(4, 2, slave=1)
        assert rr.registers[0] == 17
        assert rr.registers[1] == 17
    except ModbusIOException:
        pass