code: def setUp(self):
      tmpdir = tempfile.gettempdir()
      self.dir = os.path.join(tmpdir, "dir")
      self.dir_same = os.path.join(tmpdir, "dir-same")
      self.dir_diff = os.path.join(tmpdir, "dir-diff")
  
      # Another dir is created under dir_same, but it has a name from the
      # ignored list so it should not affect testing results.
      self.dir_ignored = os.path.join(self.dir_same, ".hg")
  
      self.caseinsensitive = os.path.normcase("A") == os.path.normcase(
          "a"
      )
      data = "Contents of file go here.\n"
      for dir in (
          self.dir,
          self.dir_same,
          self.dir_diff,
          self.dir_ignored,
      ):
          shutil.rmtree(dir, True)
          os.mkdir(dir)
          subdir_path = os.path.join(dir, "subdir")
          os.mkdir(subdir_path)
          if self.caseinsensitive and dir is self.dir_same:
              fn = "FiLe"  # Verify case-insensitive comparison
          else:
              fn = "file"
          with open(
              os.path.join(dir, fn), "w", encoding="utf-8"
          ) as output:
              output.write(data)
  
      with open(
          os.path.join(self.dir_diff, "file2"), "w", encoding="utf-8"
      ) as output:
          output.write("An extra file.\n")
  
imports: import filecmp
  import os
  import shutil
  import tempfile
  import unittest
  from test import support
  from test.support import os_helper
label_desc: Use image node_id 1 for calling the DirCompareTestCase obj's underlying member method code with example usage: obj.setUp() without return types