如何使用Apache Kafka修复Python2.7中的“AssertionError：Value必须为字节”错误

I'm new at Apache Kafka technology. I'm trying to send messages as JSON object to a kafka topic by using python 2.7 but i got "AssertionError: Value must be bytes" error. I can send messages as string succesfully, i can see my messages with kafka-console-consumer.sh. I'm using apache kafka 2.10-0.8.2.1 version. I'm giving my code below.I'm new at Apache Kafka technology. I'm trying