code: def attribute_difference(att_diff):
      """The attribute distance."""
  
      ret = 0
      for a_value, b_value in att_diff:
          if max(a_value, b_value) == 0:
              ret += 0
          else:
              ret += (
                  abs(a_value - b_value) * 1.0 / max(a_value, b_value)
              )
      return ret * 1.0 / len(att_diff)
  
imports: import math
  import random
  from copy import deepcopy
  from functools import total_ordering
  from queue import PriorityQueue
  import numpy
  from scipy.linalg import LinAlgError, cho_solve, cholesky, solve_triangular
  from scipy.optimize import linear_sum_assignment
  from sklearn.metrics.pairwise import rbf_kernel
  from nni.utils import OptimizeMode
  from .graph_transformer import transform
  from .utils import Constant
  from .layers import is_layer
label_desc: Use image node_id 2 for calling a global function with example usage: attribute_difference(att_diff) and returns: unknown