code: def compute(self, rank_above, negative_num):
      return np.mean((negative_num - rank_above) / negative_num)
  
imports: import numpy
  from openrec.tf1.utils.evaluators import Evaluator
label_desc: Use image node_id 2 for calling the AUC obj's underlying member method code with example usage: obj.compute(rank_above, negative_num) and returns: np