comefrom: <doocs>0101.Symmetric Tree_1.py
code: def dfs(root1, root2):
      if root1 is None and root2 is None:
          return True
      if root1 is None or root2 is None or root1.val != root2.val:
          return False
      return dfs(root1.left, root2.right) and dfs(root1.right, root2.left)
masked: def sample_funcname ( var_1 , var_2 ) :
      if var_1 is None and var_2 is None :
          return True
      if var_1 is None or var_2 is None or var_1.val != var_2.val :
          return False
      return var_0 ( var_1.left , var_2.right ) and var_0 ( var_1.right , var_2.left )
  