code: def click_save(self):
      if self.__recognizer.save_knowledge() is not True:
          messagebox.showwarning(
              "Recognition - Knowledge Saving",
              "Knowledge represented by self-organized feature map has been created "
              "because training has been performed. Please train recognizer and after save result of training.",
          )
  
imports: from pyclustering.nnet.som import som, type_conn
  from pyclustering.samples.definitions import IMAGE_DIGIT_SAMPLES
  from pyclustering.utils import read_image, rgb2gray
  from tkinter import *
  from tkinter import messagebox
  import math
  import pickle
  import os
  import random
label_desc: Use image node_id 5 for calling the digit_application obj's underlying member method code with example usage: obj.click_save() without return types