code: def test_directory_structure(self):
      content1 = 'print("Hello from file1")'
      content2 = 'print("Hello from file2")'
      os.mkdir(os.path.join(self.test_dir, "subdir"))
      self.create_file("sample1.py", content1)
      self.create_file(os.path.join("subdir", "sample2.py"), content2)
      loc = count_loc(self.test_dir)
      self.assertEqual(loc, 2)
  
imports: import os
  import sys
  from io import StringIO
  from keras.testing import test_case
  from keras.utils.code_stats import count_loc
label_desc: Use image node_id 11 for calling the TestCountLoc obj's underlying member method code with example usage: obj.test_directory_structure() without return types