code: def __call__(self, path, parent, children):
      self.call_log += [(path, parent, children)]
  
file_path: tensorflow/tensorflow/tools/common/traverse_test.py
imports: from tensorflow.python.platform import googletest
  from tensorflow.tools.common import test_module1
  from tensorflow.tools.common import test_module2
  from tensorflow.tools.common import traverse
label_desc: Use image node_id 2 for calling the TestVisitor obj's underlying member method code with example usage: obj.__call__(path, parent, children) without return types