code: def dInd_calc(TNR, TPR):
      
      try:
          result = math.sqrt(((1 - TNR)**2) + ((1 - TPR)**2))
          return result
      except Exception:
          return "None"
docs: Calculate dInd (Distance index).
  
      :param TNR: specificity or true negative rate
      :type TNR : float
      :param TPR: sensitivity, recall, hit rate, or true positive rate
      :type TPR : float
      :return: dInd as float