code: def tree_difference(a, b):
      """Compare TreeNodes A and B, and create a TreeDifference instance."""
      return _do_tree_difference(a, b, "", True)
  
imports: import os
  import os.path
  import stat
  import sys
label_desc: Use image node_id 2 for calling a global function with example usage: tree_difference(a, b) and returns: _do_tree_difference