code: def test_capacity_space(self):
      capacity = self.hdfs.get_capacity()
      space_used = self.hdfs.get_space_used()
      disk_free = self.hdfs.df()
  
      assert capacity > 0
      assert capacity > space_used
      assert disk_free == (capacity - space_used)
  
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 6 for calling the HdfsTestCases obj's underlying member method code with example usage: obj.test_capacity_space() without return types