code: def test_download_upload(self):
      base_path = pjoin(self.tmp_path, "upload-test")
  
      data = b"foobarbaz"
      buf = BytesIO(data)
      buf.seek(0)
  
      self.hdfs.upload(base_path, buf)
  
      out_buf = BytesIO()
      self.hdfs.download(base_path, out_buf)
      out_buf.seek(0)
      assert out_buf.getvalue() == data
  
imports: import os
  import random
  from io import BytesIO
  from os.path import join
  import numpy
  import pytest
  import pyarrow
  from pyarrow.tests import util
  from pyarrow.tests.parquet.common import _test_dataframe
  from pyarrow.tests.parquet.test_dataset import _test_write_to_dataset_with_partitions, _test_write_to_dataset_no_partitions
  from pyarrow.util import guid
label_desc: Use image node_id 15 for calling the HdfsTestCases obj's underlying member method code with example usage: obj.test_download_upload() without return types