code: def test_read_whole_file(self):
      path = pjoin(self.tmp_path, "read-whole-file")
  
      data = b"foo" * 1000
      with self.hdfs.open(path, "wb") as f:
          f.write(data)
  
      with self.hdfs.open(path, "rb") as f:
          result = f.read()
  
      assert result == 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 19 for calling the HdfsTestCases obj's underlying member method code with example usage: obj.test_read_whole_file() without return types