docs: function topicsToPartitionAssignment(topicsInfo, topics, atTimestamp, defaultOffset = -1) {
      topics = _.isArray(topics) ? topics : topics.split(',');
  
      // This will be merged into the partition assignment, to either have the assignment
      // start from atTimestamp if given, else defaultOffset.
      const defaultResumePosition = atTimestamp ? {timestamp: atTimestamp} : {offset: defaultOffset};
  
      // Find the topic-partition metadata we want
      return _.flatten(
          topicsInfo.filter(t => _.includes(topics, t.name))
          // Map them into topic, partition, merging in the
          // defaultResumePosition of either timestamp or offset.
          .map(
              t => t.partitions.map(
                  p => Object.assign({topic: t.name, partition: p.id}, defaultResumePosition)
              )
          )
      );
  }