code: def IBA_calc(TPR, TNR, alpha=1):
      
      try:
          IBA = (1 + alpha * (TPR - TNR)) * TPR * TNR
          return IBA
      except Exception:
          return "None"
docs: Calculate IBA (Index of balanced accuracy).
  
      :param TNR: specificity or true negative rate
      :type TNR : float
      :param TPR: sensitivity, recall, hit rate, or true positive rate
      :type TPR : float
      :param alpha : alpha coefficient
      :type alpha : float
      :return: IBA as float