code: def CI_calc_agresti(item1, item2, CV=1.96):
      """
      Calculate confidence interval using Agresti-Coull method.
  
      :param item1: parameter
      :type  item1: float
      :param item2: number of observations
      :type item2: int
      :param CV: critical value
      :type CV:float
      :return: confidence interval as tuple
      """
      try:
          item3 = item2 * item1
          mean = (item3 + (CV**2) / 2) / (item2 + CV**2)
          error = math.sqrt(mean * (1 - mean) / (item2 + CV**2))
          CI_down = mean - CV * error
          CI_up = mean + CV * error
          return (CI_down, CI_up)
      except Exception:
          return ("None", "None")
  
file_path: pycm/pycm/pycm_ci.py
imports: from __future__ import division
  import math
label_desc: Use image node_id 1 for calling a global function with example usage: CI_calc_agresti(item1, item2, CV) and returns: CI_down,  CI_up, str,  str