code: def RACCU_calc(TOP, P, POP):
      
      try:
          result = ((TOP + P) / (2 * POP))**2
          return result
      except Exception:
          return "None"
docs: Calculate RACCU (Random accuracy unbiased).
  
      :param TOP: test outcome positive
      :type TOP : int
      :param P: condition positive
      :type P : int
      :param POP: population
      :type POP : int
      :return: RACCU as float