code: def OP_calc(ACC, TPR, TNR):
      """
      Calculate Optimized precision (OP).
  
      :param ACC: accuracy
      :type ACC: float
      :param TNR: specificity or true negative rate
      :type TNR: float
      :param TPR: sensitivity, recall, hit rate, or true positive rate
      :type TPR: float
      :return: OP as float
      """
      try:
          RI = abs(TNR - TPR) / (TPR + TNR)
          return ACC - RI
      except (ZeroDivisionError, TypeError):
          return "None"
  
imports: from __future__ import division
  import math
  from .pycm_util import normal_quantile
  from .pycm_interpret import *
  from .pycm_param import CLASS_PARAMS
label_desc: Use image node_id 33 for calling a global function with example usage: OP_calc(ACC, TPR, TNR) and returns: unknown, str