decodeReplicas = decoder => {
  return decoder.readInt32()
}
ListPartitionReassignments Response (Version: 0) => throttle_time_ms error_code error_message [topics] TAG_BUFFER
 throttle_time_ms => INT32
 error_code => INT16
 error_message => COMPACT_NULLABLE_STRING
 topics => name [partitions] TAG_BUFFER
   name => COMPACT_STRING
   partitions => partition_index [replicas] [adding_replicas] [removing_replicas] TAG_BUFFER
     partition_index => INT32
      replicas => INT32
      adding_replicas => INT32
      removing_replicas => INT32