code: def setUp(self):
      self.name = os_helper.TESTFN
      self.name_same = os_helper.TESTFN + "-same"
      self.name_diff = os_helper.TESTFN + "-diff"
      data = "Contents of file go here.\n"
      for name in [self.name, self.name_same, self.name_diff]:
          with open(name, "w", encoding="utf-8") as output:
              output.write(data)
  
      with open(self.name_diff, "a+", encoding="utf-8") as output:
          output.write("An extra line.\n")
      self.dir = tempfile.gettempdir()
  
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 FileCompareTestCase obj's underlying member method code with example usage: obj.setUp() without return types