<doocs>0563.Binary Tree Tilt_1.py
def sum(root):
    if root is None:
        return 0
    nonlocal ans
    left = sum(root.left)
    right = sum(root.right)
    ans += abs(left - right)
    return root.val + left + right
def sample_funcname ( var_1 ) :
    if var_1 is None :
        return 0
    nonlocal var_4
    left = var_0 ( var_1.left )
    right = var_0 ( var_1.right )
    var_4 += abs ( left - right )
    return var_1.val + left + right
