code: def IBA_alpha(self, alpha):
          
          try:
              IBA_dict = {}
              for i in self.classes:
                  IBA_dict[i] = IBA_calc(self.TPR[i], self.TNR[i], alpha=alpha)
              return IBA_dict
          except Exception:
              return {}
docs: Calculate IBA_alpha score.
  
          :param alpha: alpha parameter
          :type alpha: float
          :return: IBA_alpha score for classes as dict