code: def buffer(self):
      return self._buffer
  
imports: from __future__ import absolute_import
  import collections
  import copy
  import logging
  import threading
  import time
  import kafka.errors
  from kafka.producer.buffer import SimpleBufferPool
  from kafka.producer.future import FutureRecordMetadata, FutureProduceResult
  from kafka.record.memory_records import MemoryRecordsBuilder
  from kafka.structs import TopicPartition
label_desc: Use image node_id 8 for calling the ProducerBatch obj's underlying member method code with example usage: obj.buffer() and returns: self