decode = async rawData => {
  const decoder = new Decoder(rawData)
  return {
    responses: decoder.readArray(decodeResponses),
  }
}
Offsets Response (Version: 0) => [responses]
  responses => topic [partition_responses]
    topic => STRING
    partition_responses => partition error_code [offsets]
      partition => INT32
      error_code => INT16
      offsets => INT64