code: def testVisualizeOnExistedFigureWithContent(self):
      figure = plt.figure()
      axis = figure.add_subplot(121)
      axis.plot(
          range(0, 10, 1),
          range(0, 10, 1),
          marker="o",
          color="blue",
          ls="",
      )
  
      sample = read_sample(SIMPLE_SAMPLES.SAMPLE_SIMPLE1)
  
      visualizer = cluster_visualizer(size_row=2)
      visualizer.append_clusters([sample])
      visualizer.show(figure)
      visualizer.close(figure)
  
imports: import unittest
  import matplotlib
  import matplotlib.pyplot
  import numpy
  import random
  from pyclustering.samples.definitions import SIMPLE_SAMPLES, FCPS_SAMPLES
  from pyclustering.utils import read_sample
  from pyclustering.cluster import cluster_visualizer
  from pyclustering.cluster.dbscan import dbscan
  from pyclustering.cluster.cure import cure
label_desc: Use image node_id 21 for calling the Test obj's underlying member method code with example usage: obj.testVisualizeOnExistedFigureWithContent() without return types